The Quadgrow Self Watering Planter

Earlier this year, Greenhouse Sensation sent me a Quadgrow Self Watering Planter to try.  If you’ve not seen a Quadgrow before, it’s a plastic container growing system (made from recycled plastic) that uses capillary action to provide plants with automatic watering.  This clever design alters the way we irrigate plants.  Instead of watering plants in the traditional sense (watering plants from above with a watering can), with the Quadgrow we deliver the water and nutrients right where they’re needed – at the plants’ roots.  The only watering that Quadgrow gardeners need to do is to fill up their Quadgrow’s reservoir, to provide their plants with automated watering over the next week or two.

The Quadgrow’s reservoir holds 30 litres of water, which (when the Quadgrow’s fertiliser, Nutrigrow, is added) provides a substantial quantity of water and nutrients.  Thanks to this reservoir, Quadgrow grown plants need watering on fewer occasions than traditionally grown container grown plants, which saves the gardener time, all the while ensuring that the plants have the optimum amount of water and nutrients they require for healthy growth.

As a result, the Quadgrow is a great purchase for gardeners who don’t always have time for watering but still wish to grow a bumper harvest of vegetables or fruit.  If you work away from home, have a busy lifestyle, work long hours, or enjoy holidays or weekends away, the Quadgrow Self Watering Planter will keep your plants watered and fertilised in your absence.

Those of us who have ever gardened on a balcony will know that it can become difficult to water your balcony plants without giving your neighbours below an unpleasant and rather muddy shower!  Balcony grown plants can dry out more rapidly than plants grown at ground level; so it can be more challenging to keep the plants on your balcony hydrated.  A Quadgrow Self Watering Planter would be a very useful addition for a gardener with a balcony garden.  The Quadgrow’s reservoir holds onto all of the water and nutrients; so there’s no worry or risk of dripping water onto your neighbours below and you can relax in the knowledge that your plants’ roots have access to the water and nutrients in the Quadgrow’s reservoir at any time of day or night.

Quadgrow grown plants have more resilience during periods of hot weather and exposure to drying winds, as these plants can access the water and nutrients in the Quadgrow’s reservoir whenever they need to.  Quadgrow grown plants don’t need to wait to be watered; these plants have the components they require for healthy growth, without any fluctuations in moisture and nutrient levels.

The Quadgrow is an incredibly useful system for gardeners who struggle to manage the physical side of watering; as Quadgrow grown plants need watering less often than regular container plants.  If you’re unable to water your plants yourself, but you have any kind of assistance on a regular basis, the Quadgrow could enable you to grow a bountiful harvest, without any worry or concerns about watering your plants.  Filling up the Quadgrow’s reservoir is a simple and straight forward task; as a consequence, if you need help with watering, you’ll only require a few moments of assistance, every week or so.  The person filling up your Quadgrow doesn’t need to know anything about plants, they just need a watering can and the two bottles of Nutrigrow fertiliser (which are part of the package when you purchase a Quadgrow).

NB. Towards the end of this article, I’ve written about some of the adaptions that could allow the Quadgrow to be filled up on fewer occasions – perhaps only once or twice, during the growing season.

How to assemble the Quadgrow Self Watering Planter:

It’s easy to put the Quadgrow together.  First, decide on where you’re going to position your Quadgrow; find a patio or level area of ground, where there’s room for the Quadgrow’s two reservoirs to be placed side by side; as you can see in my pictures below.  Assemble your Quadgrow in your chosen destination (a balcony, terrace, patio, etc.) as this will be easier for you than needing to move the Quadgrow at a later stage.

At the time when I was putting my Quadgrow together, we were still experiencing frosts, yet I didn’t have room inside my glasshouse for my Quadgrow, as it was full of other plants for my Trials.  As a result, here you can see my Quadgrow being assembled in my lounge:

This is the Quadgrow Self Watering Planter’s 30 litre reservoir, which is a substantial size.  However, when you’re setting your Quadgrow up for the first time, you don’t add any water or fertiliser to the reservoir.  When the Quadgrow is assembled and planted, the plants should be watered traditionally (from above with a watering can).  Then, when the compost dries out and needs watering again (around a week later), you then fill up the Quadgrow’s reservoir.  So, the important thing to remember when you’re setting up your Quadgrow, is to leave the reservoir empty for the time being.

When the Quadgrow is not in use, the parts can be separated and detached from one another, which will allows for easier storage.  However, the four Quadgrow planters and the two reservoirs need to remain connected at all times while plants are growing and the Quadgrow is in operation.  The Quadgrow’s four planters must be placed in a row or a line, as you can see in all of my pictures.  It’s not possible to have a front and back row, or to use the planters individually or in twos or threes; all four planters should be planted and positioned side-by-side.

The Quadgrow’s reservoir holds onto all the water and nutrients you give to your Quadgrow grown plants.  No water or fertiliser drains away – nothing is wasted – the water and nutrients that the plants haven’t used remain contained within the reservoir, where they’re held for later use by your plants.  This differs from traditionally grown container plants, where we water the plants from above; the water travels through the compost and the excess water runs out the bottom of the pot, onto the ground, where the water and nutrients are lost.

Quadgrow grown plants use far less water than traditional container plants.  Unlike traditional container plants, Quadgrow grown plants can access water and nutrients from the Quadgrow’s reservoir anytime they need to; whether that’s in the morning, the evening, or during the heat of the day.  So as long as you top up your Quadgrow’s reservoir at regular intervals, (check the reservoir each week, if you’re not away from home) your plants will have all the nutrients and water they require for healthy growth.

The Quadgrow’s FeederMat is designed to be inserted through the hole at the base of the pot.  When adding the FeederMats, ensure that you orientate the fabric so that the pointed end of the FeederMat is poking upwards out of the base of the planter, so it’s pointing skywards, towards your plant.  The straight edge of the FeederMat should be facing downwards, as this part of the FeederMat rests inside the reservoir, where it draws up water and nutrients to the plant’s roots above.  I took pictures showing both the right way to insert the FeederMat and the wrong way.  Unfortunately, my picture showing the correct method, with the pointed end of the FeederMat sticking up was a blur, so here instead is the wrong way to do it!

When planting the Quadgrow, make sure that your plant’s roots are in contact with the pointed end of the FeederMat; this will enable the roots to take up water from the reservoir, as required.

When you plant your tomatoes (or whatever crops you’re growing) inside the Quadgrow, plant one tomato plant per planter and make sure that the Quadgrow’s FeederMat is in contact with your plants’ roots.

After planting your tomatoes in your Quadgrow, the next step is to gently water your tomato plants.  Use a watering can and wet the compost in each of your Quadgrow’s planters.  Don’t fill up the Quadgrow’s reservoir for the moment.  When the compost around your tomato plants has dried out (in a few days or a week’s time), it’s the right time and you’re ready to fill up the Quadgrow Self Watering Planter’s reservoir with water.

At this stage, you may or may not need to add Nutrigrow fertiliser to your Quadgrow’s reservoir.  Quadgrow recommend that you add Nutrigrow fertiliser around the time when the plants’ compost has a week or so left before it runs out of nutrients.  Therefore, if you’re using a compost that contains enough fertiliser for six weeks’ growth, you would add the Nutrigrow when the compost is five weeks old.  Check the packaging on your compost for more information.

What compost can you use with the Quadgrow Self Watering Planter?

I am a peat-free gardener.  I opted to use Gardman Country Smart Multi-Purpose Organic Compost in my Quadgrow.  I chose this particular compost, as Greenhouse Sensation recommend that the Quadgrow is filled with a standard compost; the company advise gardeners to steer clear of water retentive composts and rich composts with lots of nutrients, when planting up their Quadgrow Self Watering Planters.  Gardman Country Smart Multi-Purpose Organic Compost is a peat-free, coir compost.

Earlier this year I purchased a batch of Gardman Country Smart Multi-Purpose Compost for my Compost Trials.  At the time when I was planting my Quadgrow, the Gardman Country Smart Multi-Purpose Organic Compost was performing terribly in one of my Compost Trials.  However, during my Compost Trial, I had established that this compost blend was not rich in nutrients, so it seemed like the ideal choice of growing media to use in my Quadgrow.

In addition, I was able to use the Gardman compost to more accurately discover how effective the Quadgrow’s Nutrigrow Fertiliser is, having recently seen some of this same batch of Gardman Country Smart Multi-Purpose Organic Compost perform so badly in my recent Compost Trial.  If you’re interested in Gardman Country Smart Multi-Purpose Organic Compost, you’ll find every article I’ve written about this compost blend by clicking this link.

How do you fill up the Quadgrow’s reservoir?

When it comes to filling up your Quadgrow’s smart reservoirs, it’s easiest to do this using a large watering can, without a rose or any kind of attachment on the spout.  Lift off the reservoir’s access cover, (you’ll find the reservoir’s access point between the two planters) and use a watering can (or a jug) to fill up the reservoir.  When you’ve finished adding water or fertiliser, it’s important to remember to replace the access cover, as this cover prevents water loss from evaporation, and stops anything falling into the reservoir, it also helps to prevent entry from pests and diseases.

For best results, check your Quadgrow’s reservoir regularly (once a week) and top up with water and nutrients as necessary.  There’s no need to wait until the water levels inside your reservoir have dropped to low levels before topping up your reservoir again.  In fact, it’s far better for your plants if you maintain higher water levels within your Quadgrow’s reservoir.

Don’t let your Quadgrow’s reservoir run dry.  Top up your Quadgrow’s reservoir before you leave for your holiday and fill it up again when you return from your travels.

Growing tomatoes in the Quadgrow

The ‘Honeycomb’ tomato plants that I grew in my Quadgrow for this Trial were grown from seeds that I purchased from Pennard Plants.  All of my ‘Honeycomb’ tomato seeds that were sown for this Tomato Compost Trial were sown in small individual pots filled with a 50:50 ratio of the same two composts.  Instead of using an evenly mixed blend of these composts, I opted to fill the containers with a top layer of Dalefoot Composts Wool Compost for Seeds (if you’re interested in this compost, you can find more articles I’ve written about Dalefoot Composts Wool Compost for Seeds by clicking here) and a lower layer of Dalefoot Composts Wool Potting Compost (if you’re interested in this compost, you can find more articles I’ve written about Dalefoot Composts Wool Potting Compost by clicking here).  All of the ‘Honeycomb’ tomato seeds that were grown for this Compost Trial were started off in the same sized pots, which were filled with the same ratio of these two composts.  This created strong and sturdy, healthy plants to begin my Tomato Compost Trial.

I must say, that I chose four ‘Honeycomb’ tomato plants for my Quadgrow that were dramatically smaller in size than the ‘Honeycomb’ tomato plants that were planted in my other trialled tomato composts.  The ‘Honeycomb’ tomato plants that I planted in the other trialled composts were much larger and were all very uniform in size.  However, after planting up my other planters, I was left with only three of the larger sized tomato plants and many smaller tomato plants; so I opted to plant my Quadgrow with four of the smaller ‘Honeycomb’ plants.

I planted up my Quadgrow in April 2020, when the temperatures outside were still cold (especially at night) and we were experiencing occasional frosts.  At this time, my Access Garden Products Exbury Classic Growhouse was packed full of the other tomato plants I was growing for my various Tomato Trials (along with other edible plants); as a result, unfortunately, I didn’t have room for the Quadgrow inside my glasshouse.  Accordingly, in order to protect these Quadgrow grown ‘Honeycomb’ tomato plants from frost, I opted to keep my Quadgrow in prime position, inside my lounge, for just over a month.  My lounge provided less than ideal growing conditions, with much lower light levels than I would have wished for my Quadgrow grown plants but it was the best I could offer the plants in the circumstances.

When all risk of frost had passed (at the end of May), my Quadgrow was then moved outside to my patio.  Usually, I harden off my glasshouse grown plants, by gradually moving the plants outside in the mornings and then bringing the plants back undercover again in the evening.  Taking time to harden off your plants is really beneficial.  Usually I opt to move my plants around to gently acclimatise the plants to their new outdoor environment, for a minimum of two weeks (and up to four weeks), before the plants are moved to their permanent outdoor location.

However, I was unable to move the planted Quadgrow myself, so on this occasion, all of the ‘Honeycomb’ tomato plants that were grown for this Tomato Compost Trial were all moved outside on the 25th May 2020.  None of my tomato plants were hardened off this year.  This is not something I’d recommend you try – gently acclimatising your plants and hardening off your plants before they move to their new outdoor growing conditions, is a much better practice that raises stronger, healthier plants.

On the 25th May 2020, my Quadgrow Self Watering Planter was moved outside, along with the rest of the tomato plants that I grew for this Tomato Compost Trial.  Despite being planted with much smaller sized tomato plants and enduring set-backs from six weeks of less than optimum growing conditions inside my lounge, the ‘Honeycomb’ tomato plants that I planted in my Quadgrow grew steadily and developed into substantial plants that produced an amazing harvest of delicious tomatoes, over the summer and autumn months.

Supporting tomato plants growing in the Quadgrow Self Watering Planter

Greenhouse Sensation have their own support frame for the Quadgrow (which I’ve not tried).  However, on this occasion, I decided to install a home-made support frame.  Firstly my Quadgrow Self Watering Planter was raised up onto a simple home-made wooden base that ensured that my Quadgrow was always level.  The Quadgrow has holes for bamboo canes around the top flange of the reservoir; so matching holes were drilled in my home-made wooden base and a very rustic, but sturdy, home-made bamboo support frame was made!  This support frame was created using old bamboo canes and materials I left over from other projects, as at the time, (due to COVID-19) it was impossible to purchase any bamboo canes, stakes, or wood.  I would have used newer, stronger bamboo canes, had I been given the opportunity.

To construct a reliable and effective support system for my tomato plants, I required a twine that was strong and lasting.  I needed to be certain of finding a top quality twine that wouldn’t snap or break, so to do this I used the top performing twines from my Twine Trial.

Each tomato plant that was grown for this Tomato Compost Trial was supported by its own length of strong twine that was tied into my rather rustic bamboo frame.  As the tomato plants grew larger, they were simply twirled around their length of twine, which supported the plants beautifully as they grew and meant there was no need to tie the plants in – this saves a lot of time and energy, too.

Nutrigrow fertiliser

Nutrigrow fertiliser provides plants with macronutrients, micronutrients, and trace elements.  Nutrigrow contains a blend of potassium nitrogen, phosphorous, calcium, and magnesium; plus micro-nutrients and trace elements, including: boron, copper, iron, manganese, molybdenum, and zinc.

How to use Nutrigrow fertiliser

Nutrigrow is the Quadgrow’s recommended fertiliser.  This fertiliser comes as part of the package when you purchase a Quadgrow Self Watering Planter.  Nutrigrow is a concentrated fertiliser that you dilute with tap water.  Just 6ml of Nutrigrow creates a litre of fertiliser.  The bottles of Nutrigrow that come with your Quadgrow provide enough fertiliser to fill the Quadgrow’s Smart Reservoir up fourteen times!  I still have some Nutrigrow fertiliser left over, after growing tomato plants in my Quadgrow from the 18th April 2020 until the 10th October 2020.  However, when you eventually do run out of fertiliser, additional packs of Nurtigrow, can be purchased from Greenhouse Sensation.

This fertiliser comes in two parts: Nutrigrow A and Nutrigrow B; each come with their own bottles.  The two fertilisers are kept separately and then mixed together each time you come to fill up your Quadgrow’s Smart Reservoir.  When you buy a Quadgrow, or order Nutrigrow fertiliser, the fertiliser arrives in dry powder form; Nutrigrow is supplied in sachets, with two empty bottles – one for each formula.  You simply take the sachet of Nutrigrow A and empty the contents into the ‘A’ bottle and top up with 2.5 litres of warm water; then shake the bottle to encourage the fertiliser to dissolve.  Next, take the sachet of Nutrigrow B and empty the contents into your ‘B’ bottle and top up with 2.5 litres of warm water and shake to dissolve the solution.  Now your fertiliser is ready to use.

If your plants are young, you can dilute 3ml from your bottle of Nutrigrow A and dilute 3ml from your bottle of Nutrigrow B, for every litre of water you use.  Mature plants can be given 6ml from your bottle of Nutrigrow A, and 6ml from your bottle of Nutrigrow B.  Always use equal amounts of the two fertilisers and use a stick to stir each fertiliser into your water.

Start by measuring out your water into your watering can, as you need to know how many litres of water you have, to work out how much Nutrigrow to add.  Next, with your watering can now full of water, start by adding Nutrigrow A to the water first and stir to combine.  Nutrigrow’s packaging impresses the importance of always adding the two fertilisers in the correct order, with A being the first you add, and B the second.  After adding Nutrigrow A, you add the correct quantity of Nutrigrow B to your watering can and use your stick to stir the solution again.  Always add the same quantity of the A and B Nutrigrow formulas, but add the A nutrients to the water first, followed by the B nutrients.

This fertiliser comes with its own plastic bottles, which are supplied as part of the package when you buy a Quadgrow.  When you come to place an order for a Nutrigrow re-fill, you have the option to save money (and plastic) by ordering sachets of the fertiliser to dilute in your old Nutrigrow bottles.

How often did my Quadgrow grown tomato plants need watering and fertilising?

My Quadgrow Self Watering Planter was set up and planted on the 18th April 2020.  I chose to fill my Quadgrow planters up with Gardman Country Smart Multi-Purpose Organic Compost (coir compost) that had been pre-soaked in water.  On the 17th May 2020, my Quadgrow’s reservoir was filled with tap water mixed with Nutrigrow fertiliser for the first time.  Thereafter, the Quadgrow was always filled up with Nutrigrow that was diluted with tap water.

Here you can see all of the occasions that my Quadgrow grown ‘Honeycomb’ tomato plants were watered, during spring, summer, and autumn 2020:

• 26th April 2020 – filled with tap water
• 17th May 2020 – 10l of feed
• 25th May 2020 – 30l of feed (Quadgrow moved outside)
• 7th June 2020 – 10l of feed
• 28th June 2020 – 20l of feed
• 21st July 2020 – 40l of feed – the reservoir was almost empty
• 2nd August 2020 – 40l of feed – again the reservoir was empty
• 8th August 2020 – 30l of feed
• 16th August 2020 – 30l of feed
• 5th September 2020 – 25l of feed
• 12th September 2020 – 20l of feed
• 20th September 2020 – 30l of feed
• 27th September 2020 – 20l of feed

During the summer, on two occasions my Quadgrow Self Watering Planter was allowed to become low on water and fertiliser.  When the Quadgrow was topped up on the 21st July 2020, the Smart Reservoir was found to be very low – it was almost empty.  Then on the 2nd August 2020, the Quadgrow’s Smart Reservoir was found to be empty, so the reservoir was rapidly topped up with 40l of Nutrigrow fertiliser.

The Quadgrow doesn’t waste any water or fertiliser, almost every drop that goes into the Quadgrow is used by the plants.  The water and fertiliser put into the Quadgrow is contained inside the reservoir; as there’s no hole at the bottom for the water to drain through, so no water or nutrients are wasted.

More ideas to reduce the number of times you need to fill the Quadgrow’s reservoir

I could have potentially reduced the number of times my Quadgrow grown plants needed to be watered by using the Quadgrow Mulch Cap and Cane Support Kit – a set of recycled plastic covers that are designed to fit over the top of the Quadgrow planters, where they reduce water loss from evaporation.  Naturally, there’s a space for the plant’s stem to grow through and a useful hole to support a bamboo cane.  I didn’t try Quadgrow’s Mulch Cap and Cane Support Kit this year, but I look forward to discovering how effective this product is, next year.

To further reduce the number of times your Quadgrow grown plants need watering, there is the option to purchase a Quadgrow Water Butt Link Kit, which allows you to link your Quadgrow to your water butt (you’ll need to supply your own water butt), thereby giving you a much larger reservoir to automatically water and fertilise your Quadgrow grown plants.  I’ve not tried this product myself.  However, the Quadgrow Water Butt Link Kit sounds like a very useful addition, which would be particularly valuable when it comes to holidays and weekends away, and an ideal acquisition for anyone who works or gardens away from home, (like gardeners tending allotments, school, or office gardens).

This feature could also be very beneficial for elderly or disabled gardeners, who find watering difficult, or rely on receiving help once every week or two; rather than being dependent on weekly assistance.  With a larger reservoir, these gardeners would only require assistance with watering on rare occasions, which would enable many more gardeners to experience the joy of home-grown tomatoes!

Avoiding problems with home-grown tomato plants using the Quadgrow

Tomatoes are so much fun to grow, but they’re susceptible to a number of pests, diseases, and problems.

Blossom End Rot is caused when insufficient calcium reaches the cells in the fruit.  When a plant takes in water through its roots, the water carries calcium and other nutrients from the soil to the plant.  The water and nutrients have to travel through the plant’s roots, up the stem and finally down to the fruit – the fruit is the final destination.  When a tomato plant is without the necessary water required for optimum growth, the plant becomes deficient in calcium; as although there is usually sufficient calcium in the plant’s growing media, the fruit are the last in line to receive water and nutrients and so without the necessary water, the calcium can not reach the fruit.  As a result, the underside of the tomato becomes black and sunken, due to damage suffered to the structure of cell membranes within the fruit, which was caused by the lack of calcium.

It tends to be trickier to grow tomatoes in containers, as the compost usually dries out more rapidly in a small container compared to the moisture lost among soil grown plants.  Container grown tomatoes are much more prone to Blossom End Rot than soil grown tomatoes, but in dry weather both soil and container grown plants are susceptible to this physiological disorder.  In my earlier Tomato Trial, many of my container and soil grown tomato plants suffered with Blossom End Rot.

So how did the ‘Honeycomb’ tomato plants grown in my Quadgrow fare?  Did they suffer with Blossom End Rot?  I am happy to tell you that this year, my Quadgrow grown ‘Honeycomb’ tomatoes avoided any problems with Blossom End Rot whatsoever!  This year, none of the tomatoes grown for my Tomato Compost Trial suffered with Blossom End Rot; all of my tomatoes were free from calcium deficiency.

How to avoid your home-grown tomatoes splitting

Many cherry tomatoes have very thin skins that are prone to splitting.  This is often seen on container grown plants, where the containers hold a limited supply of growing media.  Containers tend to dry out more rapidly than the soil and compost around plants grown in our garden beds and borders.  Split tomato skins is another problem that is exacerbated by irregular watering.

During this Tomato Compost Trial, I found that my Quadgrow grown ‘Honeycomb’ tomatoes produced the lowest percentage of tomatoes with split skins; compared to the ‘Honeycomb’ tomato plants that were grown in Haxnicks Vigoroot Planters, filled with the other trialled peat-free composts that featured in this Tomato Compost Trial.

How productive is the Quadgrow Self Watering Planter combined with Nutrigrow fertiliser?

I grew four Tomato ‘Honeycomb’ plants in my Quadgrow this year.  ‘Honeycomb’ is one of my favourite tomatoes, the fruit have a sensationally sweet, yet really tangy flavour, they’re utterly irresistible!  if you’re thinking of growing tomatoes next year, I’d absolutely recommend ‘Honeycomb’, it’s a wonderful tomato.

The ‘Honeycomb’ tomato plants that were grown in my Quadgrow produced their first harvest on the 28th June 2020.  The Quadgrow grown tomato plants produced a regular harvest of tomatoes every week, from the 28th June 2020 until the 10th October 2020; when the plants finally succumbed to blight.

I grew a superb harvest of ‘Honeycomb’ tomatoes in my Quadgrow this summer.  The four ‘Honeycomb’ tomato plants that were grown in my Quadgrow produced 922 tomatoes, weighing 6.4kg.  The tomato plants I grew in my Quadgrow would have produced an even larger harvest had the main stem of one of the tomato plants not been accidentally snapped.

‘Honeycomb’ is not the most productive tomato I’ve ever grown, so I am certain a much larger harvest could be attained by growing other tomato varieties in the Quadgrow.  However flavour is the most important factor for me.  ‘Honeycomb’ is one of my favourite tomatoes, as this variety produces orange coloured cherry tomatoes with an amazingly delicious flavour.  These tomatoes produce a steady harvest of tomatoes during the summer months and if you’re lucky, into autumn, too.

The full results of my Tomato Compost Trial are published in full, in my Tomato Compost Trial Report.

Quadgrow Dimensions

The Quadgrow Self Watering Planter measures 126cm long x 36cm wide (4.1′ long x 1.2′ wide).  All four planters need to be kept together, side-by-side, as both of the reservoirs support the plants growing in each of the four planters.

More Tomato Trials

I’ll be using my Quadgrow in further Trials, to see all of my articles that mention the Quadgrow, please click here.

If you’re interested in reading about my various Tomato Trials, here’s a link.

You can find more information about the Quadgrow Self Watering Planter on Quadgrow’s website – here’s a link.

More Trials and other articles that may interest you……….

For more articles about automated plant care, please click here.

To see all my Container Trials, please click here.

To see my Vegepod, please click here.

To see my mini glasshouse, please click here.