Peat Free Compost Trial 2017, Growing Broad Beans

I have found that peat free composts can vary enormously: from bags of compost filled with bark chips, which could be used as a mulch, but can’t be used as intended – as a compost to grow container plants or seedlings, right through to the other extreme – the finest quality composts, which are capable of producing prize and award winning plants, and of course, every compost in between these two polar opposites!  Over the years, I have a found rubble, glass, and even litter inside a number of the bags of compost I have purchased!  I have bought a great many bags of compost that needed to be added back to a compost bin to finish the process of breaking down the ingredients inside.  But thankfully, through my Compost Trials, I have also discovered premium quality, peat free composts, which can be used to grow top quality, award winning plants.

As many compost merchants change their compost brand names, the packaging, and the ingredients of their compost blends regularly, even if you do find a peat free compost that you favour and wish to purchase again, it can often be harder work than you wish to do so.  Indeed, you may not be absolutely certain that you have selected the particular compost that you set out and intended to purchase.

Although I have been a passionate advocate of peat free composts for many years now, I do understand gardeners’ concerns over switching to a peat free compost.  I understand that a gardener who currently uses a peat based compost, a compost that they like and are familiar with, a growing medium that they have achieved good results with in their own garden, or at their allotment, then the said gardener may well be reluctant to switch to a peat free compost – to venture into the unknown!  None of us want to start the gardening season off on the wrong foot, to be unnecessarily delayed, or compromised by using gardening products that are not as effective as we might wish for.  I want to help every gardener to avoid this dilemma, and to encourage you to switch to a peat free compost, which you can be confident and excited about using!

I also understand that if a gardener has experienced negative results with a peat free compost in the past, that they may not be enthused to try peat free compost again.  Indeed,  based on a past negative experience, this gardener might be against the idea of using peat free growing mediums in future.  It’s no good simply telling gardeners to use a peat free compost and all will be well, as this is not helpful, accurate, or informative.  We need to demonstrate the attainable gardening successes ourselves, by highlighting the finest peat free growing mediums available, and to assist, advise, and encourage other gardeners to garden more sustainably.

It can be tempting to think that we as individuals cannot possibly make a difference to this beautiful planet ourselves.  We might placate ourselves with the thought that one person who switches to a peat free compost from a peat based compost will make no difference whatsoever to the world.  However, peat is a precious resource, and peatlands are a vital part of our environment.  If optimum conditions occur, a single millimetre of peat can be created over the course of a year – this is not a resource that can be replaced in a hurry!  Indeed, very often the necessary conditions: the ideal temperatures, necessary acidity levels, sufficient moisture, the required moss species, and the adequate growth of these required mosses, combined with the ideal light quality required for these mosses to grow and develop, to allow peat to be created are not present, and so new peat is not produced.

I want to help you to experience premium quality, peat free composts, so that you can grow fantastic plants, without contributing to the needless depletion and destruction of the planet’s precious peat bogs.  This is why I have undertaken this Peat Free Compost Trial, to test out the available peat free composts available on the market, and to share my findings with you, to enable you to effortlessly purchase, what you know will be premium quality, peat free compost products.  I will demonstrate how this selection of peat free composts performed when trialled alongside each other, under the same conditions, to help you to find the finest peat free growing mediums, so that you can enjoy optimum results in your own gardens and allotments.

Although peat has been widely used as an ingredient in commercial compost for a great many years now, it might surprise you to hear that most plants do not need to be grown in a peat based compost in order to grow or perform well.  In fact, many plants grow and perform better when they are grown without the inclusion of peat in their growing media.

Finally, I must clarify that if you’re looking to purchase a compost which does not contain any peat in its composition, then you need to look for a compost which is explicitly labelled as ‘Peat Free’.  The packaging, labelling, and descriptions displayed on compost bags can at times be confusing.  With a cursory glance, you might mistake a bag of peat based compost for a bag of peat free compost, and a compost may appear to be more environmentally friendly than it actually is at first glance!  For the avoidance of any doubt, please look for a product that is described and labelled as ‘peat free’.  All of the composts that feature in this particular Compost Trial are 100% peat free.

Peat Free Composts

Each of the composts that I chose for this trial were purchased at the same time, so as to avoid using old composts, which might have been depleted of nutrients, and to ensure a fair trial of every compost in the trial.

I chose the following peat free composts and compost blends for my trial:

  • B&Q Verve Peat Free Multipurpose Compost
  • Carbon Gold All Purpose Compost
  • Dalefoot Composts Double Strength Wool Compost
  • Dalefoot Composts Wool Potting Compost
  • Dalefoot Wool Compost for Vegetables and Salads
  • 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost
  • 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Compost for Vegetables and Salads
  • Fertile Fibre Biodynamic Demeter Multipurpose Compost
  • Fertile Fibre Multipurpose Compost
  • Fertile Fibre Vegro Multipurpose Compost
  • Miracle-Gro Peat Free All Purpose Enriched Compost
  • Sylva Grow Sustainable Growing Medium
  • Westland Gro-Sure Peat Free All Purpose Compost
  • Wickes Peat Free Multi-Purpose Compost
  • Wyevale Peat Free Multi Purpose Compost
Peat Free Composts trialled for my 2017 Peat Free Compost Trial, Growing Broad Beans.

Seeds

Broad Bean ‘Robin Hood’ seeds, sown for my 2017 Peat Free Compost Trial.

For this particular Peat Free Compost Trial, I opted to sow a Dwarf Broad Bean called ‘Robin Hood’ that I purchased from DT Brown.  I chose this particular broad bean cultivar, as it produces dwarf, compact, broad bean plants that are ideal for container growing.  If you want to grow vegetables in containers, this is a great broad bean cultivar to grow!

Broad Bean ‘Robin Hood’ seeds, sown for my 2017 Peat Free Compost Trial.

2017 Peat Free Compost Trial

I started this 2017 Peat Free Compost Trial on Saturday 18th March 2017, when six dwarf Broad Bean ‘Robin Hood’ seeds were sown in each pot of compost.  Fifteen of the same sized containers were used; the containers were each filled with one of the peat free compost blends that are listed above.

Each container of compost experienced the same conditions.  The broad bean plants were observed as they grew, and the results were monitored and recorded.

Beneficial insects

A number of beneficial insects were seen on the Broad Bean ‘Robin Hood’ plants that were grown for this 2017 Peat Free Compost Trial, including a many species of bee, ladybirds and their larvae.  None of the composts used in this Compost Trial produced plants that were any more or less attractive to beneficial insects.  Here are just a small selection of the beneficial insects that were spotted during this Compost Trial:

Bees

Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ flowers are very popular with bees. Pictured during my 2017 Compost Trial.

Harlequin Ladybird Larvae

Larvae of the Harlequin Ladybird, also known by its scientific name of Harmonia axyridis, pictured on the Broad Bean ‘Robin Hood’ plants grown for my 2017 Compost Trial.

Pests and disease

No measures or precautions were taken to protect the seeds, seedlings, plants, or the developing broad bean pods themselves from pests or diseases during any stage of this 2017 Peat Free Compost Trial.  No sprays, pellets, or any other form of pest deterrents were used at any time during this 2017 Peat Free Compost Trial.

Black bean aphid

I discovered small colonies of black bean aphids (black bean aphids, and other related dark, similarly coloured aphids, are a sap sucking insect, which weaken and disfigure plants, these insects are often virus vectors, spreading viruses from one plant to another.  Black bean aphids are also known by their scientific name of Aphis fabae) present on a few of the Broad Bean ‘Robin Hood’ plants that were grown for this trial.  I first noticed these black bean aphids on the 23rd June 2017, while the broad beans that were grown for this trial were being harvested.  I found a couple of small colonies of black bean aphids establishing themselves on the Broad Bean ‘Robin Hood’ plants that were grown in the Carbon Gold All Purpose Compost and Miracle-Gro Peat Free All Purpose Enriched Compost.  The black bean aphids I found were being farmed by ants.

At this time, I examined all of the bean plants, grown in every trialled compost blend, I found that none of the other bean plants grown in the other trialled composts had any signs of black bean aphid being present.

No steps were taken at any stage of this Compost Trial to either prevent, remove, or control the black bean aphid.  The plants were simply observed, and the observations were recorded.

If your broad bean plants are affected by black bean aphids, simply pinch out the growing tips of your broad bean plants and you’ll find that within a day or two, the offending black bean aphid population or colony will have diminished significantly.  Even a substantial black bean aphid infestation will more than likely have entirely disappeared altogether within a period of about a week at most.  The young, fresh new tip growth of broad bean plants is edible, it offers a delicious bean flavour, the young broad bean pods can also be eaten whole in their entirety – bean pods and beans together.  Broad beans are a delicious vegetable to grow!

These broad bean pods were harvested on the 23rd June 2017, from Broad Bean ‘Robin Hood’ plants that were grown in a Miracle-Gro Peat Free All Purpose Enriched Compost, for my 2017 Compost Trial.
Broad Bean ‘Robin Hood’ plants grown for my 2017 Compost Trial.

Slugs and snails

As was to be expected, slugs and snails were frequently spotted among and on the containers and the broad bean plants themselves while this Peat Free Compost Trial was running.  None of the Broad Bean ‘Robin Hood’ plants that were grown for this 2017 Compost Trial received any protection from slugs or snails during any stage of this Compost Trial.

I didn’t protect any of the Broad Bean ‘Robin Hood’ plants grown for my 2017 Compost Trial from slugs and snails, to see whether any of the plants grown in my trialled composts offered any resistance to slugs and snails.

None of the composts that were trialled for my 2017 Compost Trial seemed to offer the plants grown in their compost any protection from slugs or snails.  None of the Broad Bean ‘Robin Hood’ plants that were grown for this trial stood out as being more popular with slugs and snails than any of the other plants.  The broad bean plants all sustained a similar level of what I would class as ‘light damage’ from slugs and snails, there was never a sustained attack on any particular group of plants, all of the plants experienced a few nibbled leaves, but the plants themselves remained intact.

Despite the fact that none of the Broad Bean ‘Robin Hood’ plants grown for this Compost Trial received any protection from slugs and snails, and even the slugs and snails that were spotted, were not removed, a good harvest of broad beans was generated by the broad bean plants grown in most of the trialled composts.

Although the Broad Bean ‘Robin Hood’ plants grown for this Compost Trial sustained some damage from slugs and snails, not one of the broad bean plants that were grown for this trial was entirely consumed by either slugs or snails.  The bean plants that didn’t produce a good harvest were not in any way impinged, or prevented from doing so by slugs, snails, or indeed any other pests.

The Broad Bean ‘Robin Hood’ plants that were grown in the worst performing trialled compost – Wickes Peat Free Multi-Purpose Compost, did not achieve a harvest because of the quality of the compost they were grown in, not because of any damage the plants endured from slugs and snails, or any other pests.  Indeed all six broad bean seeds germinated in the Wickes Peat Free Multi-Purpose Compost.  The plants remained intact, but they were without the necessary nutrients required to sustain the plants to grow sufficiently strongly to be able to flower and produce a harvest.

If you’re interested in protecting your plants from slugs and snails, you might be interested to see the results of my Slug and Snail Trial.

The Broad Bean ‘Robin Hood’ plants grown for my 2017 Compost Trial received no protection from slugs and snails during the trial.

Germination rates

This chart shows the number of bean plants that germinated and grew in each trialled compost. Six Broad bean ‘Robin Hood’ seeds were sown in each of the trialled composts. Only three broad bean plants germinated from the six seeds that were sown in Fertile Fibre Vegro Multipurpose Compost.

Broad Bean ‘Robin Hood’ plants

In the photographs that follow, you can see the Broad Bean ‘Robin Hood’ plants that were grown in each of the different trialled compost blends, pictured at the same stages of this Compost Trial:

B&Q Verve Peat Free Multipurpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in B&Q Verve Peat Free Multi-Purpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in B&Q Verve Peat Free Multi-Purpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in B&Q Verve Peat Free Multi-Purpose Compost.

Carbon Gold All Purpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Carbon Gold All Purpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Carbon Gold All Purpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Carbon Gold All Purpose Compost.

Dalefoot Composts Double Strength Wool Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Composts Double Strength Wool Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Composts Double Strength Wool Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Composts Double Strength Wool Compost.

Dalefoot Composts Wool Potting Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Composts Wool Potting Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Composts Wool Potting Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Composts Wool Potting Compost.

Dalefoot Wool Compost for Vegetables and Salads

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Wool Compost for Vegetables and Salads.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Wool Compost for Vegetables and Salads.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Dalefoot Wool Compost for Vegetables and Salads.

50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost.

50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Compost for Vegetables and Salads

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Compost for Vegetables and Salads.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Compost for Vegetables and Salads.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Compost for Vegetables and Salads.

Fertile Fibre Biodynamic Demeter Multipurpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Biodynamic Demeter Multipurpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Biodynamic Demeter Multipurpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Biodynamic Demeter Multipurpose Compost.

Fertile Fibre Multipurpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Multipurpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Multipurpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Multipurpose Compost.

Fertile Fibre Vegro Multipurpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Vegro Multipurpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Vegro Multipurpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Fertile Fibre Vegro Multipurpose Compost.

Miracle-Gro Peat Free All Purpose Enriched Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Miracle-Gro Peat Free All Purpose Enriched Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Miracle-Gro Peat Free All Purpose Enriched Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Miracle-Gro Peat Free All Purpose Enriched Compost.

Sylva Grow Sustainable Growing Medium

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Sylva Grow Sustainable Growing Medium.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Sylva Grow Sustainable Growing Medium.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Sylva Grow Sustainable Growing Medium.

Westland Gro-Sure Peat Free All Purpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Westland Gro-Sure Peat Free All Purpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Westland Gro-Sure Peat Free All Purpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Westland Gro-Sure Peat Free All Purpose Compost.

Wickes Peat Free Multi-Purpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Wickes Peat Free Multi-Purpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Wickes Peat Free Multi-Purpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Wickes Peat Free Multi-Purpose Compost.

Wyevale Peat Free Multi Purpose Compost

Pictured on the 30th May 2017, these Broad Bean ‘Robin Hood’ plants were grown in Wyevale Peat Free Multi Purpose Compost.

Pictured on the 12th June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Wyevale Peat Free Multi Purpose Compost.

Pictured on the 21st June 2017, these Broad Bean ‘Robin Hood’ plants were grown in Wyevale Peat Free Multi Purpose Compost.

Results: Harvesting the broad beans

Total number of broad bean pods harvested from the plants grown in each compost

This chart shows the total number of Broad Bean ‘Robin Hood’ pods harvested from the plants grown in each of the trialled composts. The Broad bean ‘Robin Hood’ plants grown in Dalefoot Wool Potting Compost produced significantly more pods than the broad beans grown in the other trialled composts.

The total weight of the broad bean pods harvested from the plants grown in each compost

This chart shows the total weight of broad bean pods harvested from the broad bean plants grown in each trialled compost. The Broad bean ‘Robin Hood’ plants grown in Dalefoot Wool Potting Compost produced broad bean pods, which weighed 25% more than the second best performing compost in the trial.

The total number of broad beans harvested from the plants grown in each of the trialled composts

This chart shows the total number of broad beans harvested from the plants grown in each of the trialled composts. The Broad bean ‘Robin Hood’ plants grown in Dalefoot Wool Potting Compost came first, producing a total of 74 broad beans. The plants grown in Sylva Grow Sustainable Growing Media came second, they produced 61 broad beans. At the other end of the scale, the broad bean plants grown in Carbon Gold All Purpose Compost produced three beans, and the broad bean plants grown in Wickes Peat Free Multi-Purpose Compost failed to produce any beans at all.

The total weight of the broad beans harvested from the broad bean plants grown in each of the trialled composts

This chart shows the total weight of broad beans harvested from the plants grown in each of the trialled composts. The Broad Bean ‘Robin Hood’ plants grown in Dalefoot Wool Potting Compost produced the largest harvest of broad beans out of all of the broad bean plants grown for this trial, despite the fact that there were five broad bean plants growing in this compost, some of the other trialled composts had six broad bean plants.

Average weight of each broad bean pod produced by the broad bean plants grown in each trialled compost

This chart shows the average weight of the harvested broad bean pods, before they were shelled. The Broad Bean ‘Robin Hood’ plants grown in Sylva Grow Sustainable Growing Media produced broad beans with the heaviest average weight of 11.3g. The Broad Bean ‘Robin Hood’ plants grown in Dalefoot Wool Potting Compost and Dalefoot Vegetable and Salad Compost were close behind, in joint second place with an average weight of 11g per broad bean pod produced by the plants grown in their compost. In third place the broad bean plants grown in Miracle-Gro Peat Free All Purpose Enriched Compost, produced broad beans with an average weight of 10.4g.

Average weight of each broad bean produced by the broad bean plants grown in each trialled compost

This chart shows the average weight per harvested broad bean, from the plants grown in each of the trialled composts. Broad beans are not large in size, therefore I didn’t see a huge amount of variation in the weight of the beans – the only notable result is that the plants grown in Carbon Gold Compost produced broad beans whose average weight was significantly less than all of the other beans harvested for this trial.

The average weight of shelled broad beans harvested per plant for each of the trialled composts

This chart shows the average weight of harvested broad beans (after shelling from their pods) per plant, for the plants grown in each trialled compost. This ensures a fair result for any composts with a low germination rate and fewer plants. Dalefoot Wool Potting Compost led the field, the Broad bean ‘Robin Hood’ plants grown in this compost produced 20% more beans per plant than the broad bean plants grown in the other trialled composts.

The average number of broad beans harvested per plant, for the broad bean plants grown in each of the trialled composts

This chart shows the total number of beans harvested per plant, normalising for germination rates. As you can see, Dalefoot Wool Potting Compost led the field again, with 30% more broad beans harvested from the plants grown in this compost, than the next best performing compost in the trial.

Compost costs

The price of the composts I have trialled for this 2017 Peat Free Compost Trial vary greatly.  The following compost costs given in this Compost Trial Report reflect the prices of all of the trialled composts at the time (2017) when these composts were ordered or purchased for this Compost Trial.

When comparing the trialled composts and their cost when purchasing one bag of compost at a time, the most expensive composts that featured in this Compost Trial were produced by Dalefoot Composts.  The Dalefoot Composts cost 53 pence/litre.  The cheapest compost featured in this trial, when evaluating the cost per litre for purchasing one compost bag at a time, was the B&Q Verve Peat Free Multi-Purpose Compost, which cost 8 pence/litre.

However, these prices only apply when a customer purchases a single bag of compost at a time.  It’s worth remembering that the price of some of the more expensive (usually mail-order) composts drops when you buy in bulk.  If you buy 5 or 10 bags of Dalefoot Compost, for example, the price per litre drops by 25%, from 53p/litre to 40p/litre.  When ordering compost you can make substantial savings by clubbing together with other gardeners, fellow allotment holders, horticultural society members, friends, family, or neighbours, and making a bulk order of compost to be delivered to one address.

A bulk discount does not apply to all of the composts though; Carbon Gold All Purpose Compost costs the same regardless of the quantity purchased, meaning that this compost is by far the most expensive compost in this Compost Trial when more than one bag of compost is purchased at a time.

Although the mail-order composts that featured in this trial have generally proved themselves to be of better quality (in terms of harvest and plant health – see the results below), cost is one factor where the mail order composts can’t compete with the more widely available garden centre brands, such as Miracle-Gro and Westland.  By virtue of their many local stockists, these garden centre branded composts are available for collection, and so consequently do not incur a delivery fee, making them significantly cheaper – in some cases garden centre branded composts are a quarter of the cost of the more expensive mail-order brands.  However if you require a taxi, are unable to carry a hefty bag of compost yourself, or are simply unable to spare the necessary time required to collect your compost yourself, you will appreciate being able to purchase a top quality compost, and can enjoy the luxury of having your compost delivered directly to your garden or allotment, saving you both time and energy.

Naturally all of the composts that were purchased directly from a store each entailed a collection cost (driving, or travelling to and from a garden centre for collection) which has not been presented or detailed in this trial report, simply for the reason that the cost of collecting each of these composts can not be standardised, and would vary so greatly for each reader; but nonetheless this additional time, as well as the money spent in travelling to collect these composts should not be ignored.  It took longer than a full working day to collect and purchase the store bought composts that featured in this trial.

One way that you can get the best of both worlds – to use a superior compost without a high cost – is to mix a spent compost with a premium mail-order brand.  For example, in previous Peat Free Compost Trials, I have shown that mixing a spent compost, which was unable to sustain plant growth much beyond germination when used alone, with Dalefoot Double Strength Wool Compost, a concentrated compost made of powerful ingredients, which is designed to be used in this manner.  By combining a top quality, concentrated compost formula with your own spent compost, you can enjoy excellent results from your compost, at a greatly reduced cost.

This chart shows the price per litre for the different types of compost and for different amounts (1, 5, and 10 bags). You can see that for the compost bought at local suppliers (garden centres etc) the lack of delivery fees keeps the price low, and many of the garden centres have offers that make it cheaper to buy more (e.g. buy-one-get-one-free, three for £10 etc).
The composts that are delivered are more expensive per litre, but the way delivery is charged can significantly affect the price. For example, Dalefoot’s flat delivery rate (£5 for up to 11 bags) means that a bulk load really brings the price per litre down. This contrasts with Carbon Gold, who charge a per-bag delivery fee regardless of quantity – making their compost (which already costs £19/bag) much more expensive to buy.

Dalefoot Composts Double Strength Wool Compost

Dalefoot Composts Double Strength Wool Compost isn’t designed to be used neat from the bag, which is how I have used it in this Compost Trial.  This is a powerful, nutrient rich, concentrated compost, which can be added to spent compost to enrich the compost and create a viable growing medium.  When used in the way in which it was designed and is recommended to be used, Dalefoot Composts Double Strength Compost performs better, goes a lot further, and is far more economical to use.

2017 Peat Free Compost Trial – Growing Broad Beans Conclusions

Vicia faba ‘Robin Hood’ was grown for my 2017 Peat Free Compost Trial.

I can reveal that the best performing composts during this Compost Trial, (measured by the largest average harvest of beans per plant – to allow a fairer trial for the composts with fewer plants), were as follows:

Final Compost Trial Ranking – Harvest per Plant

For the final ranking, I have ordered the composts by average harvest weight per seedling, which will normalise for the containers where a lower germination rate occured.  This rank shows the productivity of the plants themselves.

Rank Compost Type Conclusions
1 Dalefoot Composts Wool Potting Compost was the clear winner of this Compost Trial!  The Broad Bean ‘Robin Hood’ plants that were grown in Dalefoot Composts Wool Potting Compost for this Compost Trial flourished, they produced a greater harvest of beans than any of the other broad bean plants grown for this trial.  However the results of this Compost Trial were analysed, Dalefoot Composts Wool Potting Compost came first!
2 The Broad Bean ‘Robin Hood’ plants that were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost were very productive and healthy.  The Broad Bean ‘Robin Hood’ plants that were grown in this compost blend performed consistently well throughout this particular Compost Trial.  Consequently, this 50/50 blend of Dalefoot Double Strength Wool Compost and Dalefoot Wool Potting Compost came in 2nd place during this particular Compost Trial.
3 The Broad Bean ‘Robin Hood’ plants that were grown in a blend of 50/50 Dalefoot Double Strength Wool Compost and Dalefoot Wool Compost for Vegetables and Salads were very productive, producing a high average number of beans per plant.  The Broad Bean ‘Robin Hood’ plants that were grown in this particular compost blend performed consistently well throughout this Compost Trial.  Consequently, this Dalefoot Compost blend was placed in 3rd position in this Compost Trial.
4 The Broad Bean ‘Robin Hood’ plants that were grown in Dalefoot Wool Compost for Vegetables and Salads were very productive and grew well throughout this Compost Trial.  Accordingly, Dalefoot Wool Compost for Vegetables and Salads was ranked in 4th position for this particular Compost Trial.
5 The Broad Bean ‘Robin Hood’ plants that were grown in Sylva Grow Sustainable Growing Medium for this particular Compost Trial performed well, achieving the highest average broad bean pod weight, a high total broad bean pod weight, as well as a high total number of beans.  All of the bean plants survived and were productive, but the plants grown in this compost produced a lower number of beans per plant than the higher ranking Dalefoot Composts.  Consequently, Sylva Grow Sustainable Growing Medium came in 5th place for this particular Compost Trial.
6 All of the Broad Bean ‘Robin Hood’ plants that were grown in Miracle-Gro Peat Free All Purpose Enriched Compost grew and were productive during this Compost Trial.  In this particular Compost Trial, Miracle-Gro Peat Free All Purpose Enriched Compost was ranked in 6th place, due to the rate of the average bean harvest per broad bean plant being lower than five of the other compost blends.
7 All six of the Broad Bean ‘Robin Hood’ plants that were grown in Wyevale Peat Free Multipurpose Compost grew and produced beans.  The broad bean plants that were grown in this compost performed consistently well, keeping this compost at around the middle position throughout this Compost Trial.  Wyevale Peat Free Multipurpose compost was placed 7th place for this particular Compost Trial.
8 The Broad Bean ‘Robin Hood’ plants that were grown in Fertile Fibre Biodynamic Demeter Multipurpose Compost grew and produced beans during this trial.  Fertile Fibre Biodynamic Demeter Multipurpose Compost came in 8th place during this Compost Trial, achieving this position due to the average harvest of beans per broad bean plant that were grown in this particular compost.
9 Half of the Broad Bean ‘Robin Hood’ plants that were grown in Fertile Fibre Vegro Multipurpose Compost for this Compost Trial grew and produced beans.  These Broad Bean ‘Robin Hood’ plants produced the second lowest harvest of beans during this trial.  As this harvest was normalised for the number of plants, this placed Fertile Fibre Vegro Multipurpose Compost in 9th Place for this Compost Trial.  Had the results been analysed differently, this compost may have been ranked in a lower position.
10 The Broad Bean ‘Robin Hood’ plants that were grown in B&Q Verve Peat Free Multi-Purpose Compost only managed to produce 8 pods of broad beans.  Consequently, B&Q Verve Peat Free Multi-Purpose Compost was ranked in 10th position for this particular Compost Trial.
11 All of the Broad Bean ‘Robin Hood’ plants that were sown in Westland Gro-Sure Peat Free All Purpose Compost survived, grew, and produced broad beans.  Westland Gro-Sure Peat Free All Purpose Compost was ranked in 11th place for this Compost Trial, as the harvest per plant was lower than many of the other broad bean plants grown in the other trialled composts.
12 Fertile Fibre Multipurpose Compost was ranked in 12th place for this particular Compost Trial.  This placement was achieved, as the harvest of Broad Beans per plant was lower than many of the other Broad Bean ‘Robin Hood’ plants that were grown in the other trialled composts.
13 Dalefoot Composts Double Strength Wool Compost is a very strong, concentrated compost, which has been designed to be mixed with a spent compost, which is very low, or entirely lacking in nutrients, to create a viable growing medium.  This compost is not designed to be used neat, as I have used it in this trial.  Dalefoot Composts Double Strength Wool Compost was ranked in 13th place for this Compost Trial, it was simply too strong for the plants and would have performed better if it had been used as it had been designed, mixed with a spent compost to dilute its concentration.
14 The Broad Bean ‘Robin Hood’ plants that were grown in Carbon Gold All Purpose Compost survived this Compost Trial, they grew and produced beans.  However, the harvest that these Broad Bean ‘Robin Hood’ plants produced was lower than that of the other productive bean plants grown in the other trialled composts featured in this Compost Trial, placing Carbon Gold All Purpose Compost in 14th Place.
15 All six of the Broad Bean ‘Robin Hood’ plants that were grown in Wickes Peat Free Multi-Purpose Compost survived, but barely so.  None of the Broad Bean ‘Robin Hood’ plants that were grown in this compost managed to produce a single bean.  Consequently, Wickes Peat Free Multi-Purpose Compost came last, in 15th place during this 2017 Compost Trial.

Compost Trial Conclusions

The results highlight a number of conclusions:

  • Although Dalefoot Composts is amongst the more expensive of the brands of composts that featured in this Compost Trial, the results from Dalefoot Composts Wool Potting Compost and Dalefoot Compost for Vegetables and Salads are far better than that of the other trialled composts.
  • Mixing Dalefoot Compost blends with Dalefoot Double Strength composts also produces excellent results – although using the Dalefoot Double Strength compost neat was too much for the plants.
  • For this Compost Trial I have used Dalefoot Double Strength Wool Compost neat, which is not how this compost was designed or intended to be used.  This is a powerful, concentrated compost, which is designed to be mixed and diluted with a spent compost, which is low in nutrients, to create a quality growing medium.
  • Wickes compost was the worst performing compost in this particular Compost Trial – the plants grown in this compost hardly developed at all.   No harvest was produced by the plants that were grown in this compost.  This is likely to be because the Wickes compost was comprised of a lot of woody material, which has yet to fully break down.
  • Whilst Wickes is a very inexpensive compost, the results of this Compost Trial demonstrate that spending more on your compost is worth while if you want to grow your plants to fruition and to achieve a harvest.
  • The Broad Bean ‘Robin Hood’ plants that were grown in Carbon Gold All Purpose Compost produced a very low harvest.  Given the high price of this compost (7x the cost of Wickes compost per litre) this performance is extremely disappointing.
  • The performance of the Broad Bean ‘Robin Hood’ plants that were grown in all three of the Fertile Fibre Composts were just average, despite the relatively high cost of these mail order composts.  Sadly these composts did not perform much better than the cheaper compost brands such as Westland, B&Q, and Wyevale.

Further Trials

Compost Trial Reports

To read the results of my 2017 Compost Trial Report: Vegetable Growing, please click here.

To read the results of my 2017 Compost Trial Report: Growing Calendula, please click here.

To read the results of my 2016 Compost Trial Report: Growing French Beans , please click here.

To read advice on planting up containers, please click here.

Sweet Pea Trial Reports

To read the results of my 2017 Sweet Pea Trial, please click here.

To read the results of my 2016 Sweet Pea Trial, please click here.

To read the results of my 2015 Sweet Pea Trial, please click here.

Scented Daffodil Trial Reports

To read the results of my 2018 Scented Daffodil Container Trial, please click here.

To read the results of my 2017 Scented Daffodil Trial, please click here.

Slug and Snail Trials

To see the results of my Slug and Snail Trial and discover the most effective methods to protect your plants from slugs and snails, please click here.

Terrarium, Vivarium, and Orchidarium Trials

To see how my Orchidarium was created, please click here.

To read how I track the temperature, humidity, and light conditions inside my terrariums, please click here.

To read the first part of my White Orchid BiOrbAir Terrarium Trial, please click here.

To read the first part of my Madagascar BiOrbAir Terrarium Trial, please click here.

To read the first part of my Miniature Orchid BiOrbAir Terrarium Trial, please click here.

To read about the general care I give to my orchids and terrarium plants, and the general maintenance I give to my BiOrbAir terrariums, please click here.

Other articles that may interest you…………………..

To see my 2018 Calendar of Specialist Plant Fairs, Festivals, Sales and Swaps, please click here.

To read tips and advice for growing Sweet Peas, please click here.

To read about growing mushrooms indoors, please click here.

For gardening advice, tips, and lovely ideas of what you could do in your garden, or at your allotment, in February, please click here.

For gardening advice, tips, and lovely ideas of what you could do in your garden, or at your allotment, from mid-February to mid-March, please click here.

Other articles you might like:

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