When midsummer passes us by, rhubarb production naturally slows down.  Unless you’re growing a late summer and autumn cropping rhubarb (like ‘Livingstone’), stop picking rhubarb now to allow your plants to build up their strength for next year’s harvests.  Rhubarb thrives in wet summers.  After heavy rain (or a thorough watering), spread a mulch of well-rotted manure or homemade garden compost over the soil around your plants.