Now is the time to plant new rhubarb crowns or lift and divide old ones. Rhubarb crowns are readily available from nurseries throughout winter and early spring.
Rhubarb needs:
rich, fertile, well-drained acidic soil
full sun in winter and shade in summer
heavy, infrequent watering – light overhead watering tends to make rhubarb go to seed
regular fertilising during the growing season. Rotted animal manure is best - use a weak liquid solution
a separate bed so they can be left undisturbed for up to 3 or 4 years
Rhubarb is adaptable to most climates but grows best in areas with cool winters and mild summers.
It can be grown from crowns planted in winter or early spring, or seed sown in spring in cooler climates or late summer/autumn in warmer areas. Do not apply fertiliser or manure at planting time.
Plant the crowns, seeds or seedlings 50-100cm apart in soil enriched with compost and blood and bone. If planting crowns, the bud or ‘eye’ should be sitting just above the soil.
If flower stalks appear, cut them off at the base, and fertilise the plant with nitrogen to encourage more leafy growth. This is a sign the plant is under stress, either lack of nutrition or moisture.
The plants should be left undisturbed for 3 or 4 years, after which they decline and become woody and/or spindly. They can be rejuvenated by lifting, dividing and replanting the crowns. Always replant the healthiest crowns and make sure they contain at least one ‘eye’
Harvesting
Pick the outside stalks first, leaving the newer inner stalks to grow. Cut the leaves from the stems, discard the leaves in the compost, and cook the stalks immediately or store in the crisper for up to one week.
How many plants?
Ten to twelve plants for the average family.
Warning! Rhubarb leaves are poisonous - they contain oxalic acid. Only eat the stems which have a much lower oxalic acid content. The use of aluminium saucepans is not recommended as the oxalic acid can dissolve the protective coating and form aluminium oxalate.