How to grow rhubarb
Great for gardeners with not much time, rhubarb are impressive looking plants that crop over a long period - especially if given a little extra help from us.
Rhubarb is a hardy perennial that lasts a long time and is easy and undemanding to grow. Although a deep rooting plant, it can be grown in large pots - old dustbins are ideal - and prefers an open, sunny spot in moist but free draining soil. When considering how to grow rhubarb, it is important to remember that rhubarb hates sitting in waterlogged soil, especially over the winter. Although hardy, those precious stems can suffer in cold weather, so keep plants well away from frost pockets.
How to grow rhubarb
Rhubarb can be grown from seed, but the best plants are grown from young, dormant crowns or divided from mature ones. They are hungry, thirsty plants, so dig in a generous helping of well-rotted, organic matter, such as your own garden compost. A good guide on how to grow rhubarb is to plant the crowns with the growing point at or just below the soil surface. This will prevent them from rotting if planted too low, or drying out if too high. To help retain moisture, mulch plants in spring with more organic matter, taking care not to bury the crown and keep plants well watered in the summer.
Another helpful tip on how to grow rhubarb is that it needs a frosty winter to produce the best stalks, so allow the foliage to die back in the autumn and then remove it to expose the growing point to the cold winter weather. As a leafy crop rhubarb needs a nitrogen feed, rather than a high potash one like fruiting crops, so give plants a boost by feeding with a general purpose fertiliser such as Growmore in the spring. Remove any flower heads as they appear in summer, and look out for the limp leaves and weak growth of the fungal disease 'crown rot'. If affected, remove stems promptly, cutting back into healthy tissue. If symptoms persist, plants may need to be dug up and binned. Finally, divide plants after five years, dividing the crown into sections with a spade.
If you are wondering how to grow the rhubarb you see in supermarkets early in the year, you can produce those sweet, tender stems yourself by forcing. Simply cover plants in mid to late winter with a layer of straw and an upturned bucket and wait until the early spring.
When to harvest rhubarb
One of the most important things to consider about harvesting rhubarb is that you do not pick it in its first season, and only do so lightly the second year, to ensure you don't weaken the crown. From then on, the only rules concerning when to harvest rhubarb are to pull just a few stems at a time and never more than half in one go - this ensure there are always stems left on the plant that are in active growth, and also to stop picking by mid summer or your crop will suffer the following year.
Always harvest stems by pulling and firmly twisting, rather than cutting, as this can leave behind stumps that are very susceptible to rot. If forcing, you can tell when to harvest rhubarb when the stems reach the top of the bucket or container, usually about three weeks earlier than those grown uncovered. Don't pick from a forced crown again that season, but leave your plant to recover for the following year.