Should I use a particular type of rhubarb for forcing?
Is it essential to chit seed potatoes? Rona Allbright, by email Robin Houghton, by email
Stefan says: Seed potatoes can be sprouted or ‘chitted’ prior to planting by placing the tubers on a tray with the ‘rose’ end uppermost. This end has the most eyes or buds and sprouts arise from them. Chitting tubers extends the growing period, giving earlier crops and higher yields, particularly with early potatoes. For larger quantities, particularly of maincrop potatoes, it may not be practical to chit potatoes.
Trays should be placed in a cool, frost-free place with moderate light, such as an unheated room, but avoid direct sunlight. After about six weeks, shoots should be 5cm long and dark coloured. If kept too warm and dark, pale, leggy shoots form, which make planting difficult. For early potatoes choose four strong shoots and rub off the weaker shoots but there’s no need to thin shoots for later crops.
Stefan says: Forcing provides an early harvest of tender, pink rhubarb. This is done by covering the crowns in January or February with a layer of straw and placing an upturned bucket or clay rhubarb pot over it to exclude light. Stalks will be ready to pull about three weeks earlier than uncovered crowns. Crowns that have been forced for earlier harvest are generally left without pulling for the rest of that season.
For an even earlier harvest, commercial growers in Yorkshire lift roots in early winter and plant them in special rhubarb houses so the new shoots can be brought on. The home gardener can replicate this by lifting crowns, potting them up and placing in a cool room or greenhouse at a temperature of between 7–16C. Exclude light with buckets and keep the pots just damp. Stalks can be harvested in about five weeks. Crowns must not be lifted too early until they’ve received sufficient winter chilling to break bud dormancy. In cold areas, mid-December is probably soon enough but it’s better to delay in mild areas. ‘Timperley Early’ is one of the best, but also try ‘Stockbridge Arrow’ and ‘Victoria’. Crowns forced in this manner are usually discarded after harvest.