Thanks to John Harrison of Allotment & Gardens
Lemongrass resembles a tall, grassy-like scallion because it is a member of the grass family. The slightly bulbous base is used in Asian cooking, particularly Thai, and the long, sharp-edged lemon-scented leaves are popular for teas and flavourings. They are an attractive but tender perennial plant that is easily started from seed or propagation, and will grow quickly with heat. Wintering lemongrass with care and a warm place will keep the plant producing more tender shoots.
Recommended Varieties
Most started plants are unlabelled as to type.
- Cymbopogon citratus is the popular and common variety for cooking and teas.
- Cymbopogon flexuosus is also used for cooking and teas
- Cymbopogon nardus or C. Winterianus, with it’s noticeable red stems, is primarily grown for oil production for flavourings and fragrances.
Pests and Problems
There are no known pests to date. But dehydration and less than 6 hours sunlight daily will set the plant back. Plant caregivers unfamiliar with this grass might cut or pull it thinking it is regular grass.
Sowing and Growing
Lemongrass is easily started from seed, but the seed must be kept refrigerated or very cool at all times for germination and storage. If you purchase new seed, it should be refrigerated for about 4 weeks first to encourage germination. Start seeds indoors in late winter to plant out after danger of frost has passed.
Plants can be purchased or small clumps obtained for further division. Plants grow in clumps and do not send out runners.
Like most grasses, lemongrass prefers warmth, full sun, and rich, moist but free draining soil. It cannot tolerate standing water. Being a grass, some monthly high nitrogen fertilizer or chicken manure pellets help plant vigour
Plants can grow to 3 ft tall so site with care and place markers. Space outdoor plants 2-3 ft apart.
They can also be container grown in large pots to house their large, thick root mass. Repotting may be needed. Does not thrive as a strictly indoor plant.
If the potted plant becomes too large, it is easily divided with a spade as you would a hosta. Trim the leaves (save these for teas) quite short and repot.
Lemongrass can also be propagated from shop purchased shoots. Place shoots in a glass of water and change the water every day. In 3-4 weeks you’ll have roots about 2” long. Pot the shoots, several to a pot, in some good potting loam and keep evenly moist in full sun.
Harvesting, Eating and Storing
Harvest when plant is 4-8 months old, or, about one foot tall. Afterwards, you can harvest every 3-4 months (kept indoors in less temperate areas) for about 4 months. To continue plant growth, cut the entire stalks below the white swollen ends and keep soil moist. Save fresh cuttings for teas.
Lemongrass is best used fresh by cutting individual stems from the white ends (base) and discard any discoloured parts.
Dry leaves in a dry, cool place then cut into smaller pieces for teas. Dried stalks can also be stored in an airtight glass container up to one year.
The fresh leaves are very fibrous and must be chopped finely then pounded or ground a bit in mortar and pestle to release their flavour. Once the flavour is infused you can discard the chopped leaves
Note: pregnant or breast-feeding women should not eat lemongrass. Those with glaucoma should not use lemongrass oil.