Another crop suited to our temperate climate and cool winters, though it doesn’t like our long hot summers. Stem color does relate to temperature; apparently 10 degrees C prduces the brightest reds, though there are varietal differences. The best way to grow rhubard is by planting the crowns, which can be divided from mature plants, otherwise it takes at least three years from seed to ready to plant seedling. Mature plants should be divided every 4 or 5 years, like other perennials.
Autumn – Clear straw mulch, consider basalt dust as an alternative mulch.
Winter – Planting or transplanting time. Divide mature plants by lifting the dormant crowns once the leaves have died back and divide with sharp spade or knife into sections about 10-15cm wide, good healthy roots and at least a bud or two. Cover the crown with 5-10cm of soil, leaving the emerging shoot/bud just clear of the soil (as with strawberries). Space plants 60 – 80cm apart in soil that ha been well dug over, compost and lime/dolomite, rockdust added. Water in well. Harvest stalks by pulling away from the base with a sharp twist, or use a sharp knife.
Spring – Planting or transplanting time. Seedlings are available for spring planting but you can also plant crowns during early spring (see above). Mulch and feed. Add potash around the crowns, as well as compost and a foliar spray of seaweed, worm juce or fish emulsion. Continue to harvest, but leave some stalks behind to ensure the plant can continue to grow and produce.
Summer – Keep plants mulched and watered.
Generally – Rhubarb likes a well drained, fertile, sunny site with pH 5.5-6.5, so adding lime and compost every winter is a good idea. They are deep rooted plants and need regular feeding. Mulch over summer but don’t use straw mulch during winter because slugs, slaters, snails and millipedes will congregate, plus the mulch will accentuate frosts. Remember, the leaves are poisonous.
Eating – Rhubarb is welcome in late winter and early spring when there is little fresh fruit around. Stewed, baked (in orange juice, orange zest, spices, butter) and bottled.