Stem lettuce is a type of lettuce native to Asia. It has several names in Dutch, including: Asparagus lettuce, palm tree lettuce and celtuce and in Chinese it is called wosun or woju. Both the leaf and stem of this plant can be eaten. The firm leaf has a somewhat bitter taste and can be prepared as a substitute for lettuce or spinach. The stem should be peeled first and can then be prepared in pieces in stir-fry dishes, for example. The flavour of the stem is fresh-nutty. Do not let the stalks grow too big and thick, they will become woody. About 20 - 35 cm long and 3 - 5 cm thick is ideal. Non hardy annual. Height: 40 - 60 cm.
Outdoor sowing under glass: March - April
Outdoor sowing: April - June
Germination: 7 - 14 days
Germination temp.: 6 - 18 °C
Sowing depth: shallow - ½ cm
Planting distance: 35 - 40 cm
Distance between the rows: 40 cm
Planting postition: sunny - semi-shade
Days till harvest leaves: 35 - 40
Days till harvest stem: 56 - 70
Sow outdoors under protection (cold greenhouse, cold tray) from March. Sow shallowly in separate pots or in seed trays with separate cells to make transplanting easier. Use a well-moistened sowing medium. Cover the seeds with a very thin layer as this is a light germinator. Keep the temperature as even as possible and don't let the temperature drop especially at night. Plant out the seedlings 3 - 4 weeks after germination in a pre-fertilised, sunny spot with good drainage. Keep the plantlets moist and weed-free. Keep 35 - 40 cm space between the plantlets. Protect the plants from slugs and snails. Water sufficiently in case of drought.
Sow outdoors from April onwards, when severe frost is no longer expected. Sow the seeds shallowly and press them gently into the soil. Sow in a previously well-fertilised spot with good drainage. If necessary, cover with a very thin layer of soil. Keep 35 - 40 cm apart. Keep well weeded and moist.
Stem lettuce, like all other lettuces, shoots to seed quickly at higher temperatures. This can be avoided by sowing in a sunny place in spring and in a semi-shaded place in summer. Don't let the plants dry out. Both the leaf and stem of this plant are edible. The leaves can be harvested from 35 - 40 days after germination. The stems about 56 - 70 days after germination. The stem with possibly some leaves attached can be kept in the fridge for about 1 week.
