Brassica rapa var. perviridis Family: Brassicaceae
Days to Maturity: From seed – 20 days (baby greens); 40 days (full size)
Description: A biennial leafy Asian green. Moderately elliptical, dark green leaves are grown on a long stem. They are slightly textured with veining quite prominently displayed. Although a biennial, this is considered a cool season crop, although it can tolerate short periods of extreme heat. It is reasonably frost-hardy to temperatures as low as -18 °C to -12 °C (0 °F to 10 °F). Protection with row cover or in a hoop house at the low temperatures is recommended.
Special Notes: An open-pollinated variety native to Japan, Korea, and Taiwan, this mustard is closely related to cabbage, turnips, rapini, and bok choi. Originally grown exclusively in its native countries, it was introduced into North America in the 1930s but has only recently gained some popularity in the specialty markets.
Fast growing at optimum soil temperature, komatsuna can be harvested for baby greens at 20 – 30 days from seeding. Matures to full size in 40 days.
Leaves have good nutritional value, rich in beta carotene, calcium, and Vitamins A, B2, C, and K. Also highly prized for its glucosinolates…sulfur-containing compounds found in brassicas which are generally thought to have great benefits in fighting cancer.
How to Grow: Optimum soil temperature range: 7 °C – 35 °C (45 °F – 95 °F). Minimum soil temperature: 4.5 °C (40 °F). Ideal soil temperature: 29.5 °C (85 °F). Ideal soil pH: 6.0 – 6.5. Amend planting row with Complete Organic Fertilizer (click here for recipe)…one cup (250 ml) per ten feet (3 m).
If starting indoors, sow seeds from early February through to early March. If direct seeding outdoors, sow undercover for frost protection. From March through to the end of May, direct sow short rows every 2 – 3 weeks to ensure a continuous harvest of baby greens or mature plants. Start sowing again in late August or early September for late fall and winter harvests.
Cut individual leaves or the whole plant at whatever maturity stage you prefer. Young leaves are tender with a gentler flavour than the tougher mature ones. If left too long, mature leaves can develop a slight bitterness. Use in salads, stir fries, soups, or as a steamed vegetable like spinach. Can be dried for longer storage in an air-tight container in a dry cool place.
Pests & Diseases: Slugs and wood lice (sow bugs) can be a problem for young seedlings. Good housekeeping in keeping rows debris-free with no puddles of water should help with these two pests. Flea beetles are attracted to the more mature leaves, leaving tiny round holes in their wake. Using row cover will guard against this pest.
As with every member in the Brassicaceae family, clubroot is of major concern to komatsuna. Keeping to a strict regime of rotating your crops annually in a four or five year cycle…and not sowing another brassica crop where you grew one the year before is paramount to keeping clubroot out of your garden.
In our Zone 7a garden: We grew komatsuna for the first time in 2017. It grew well for us in our vegetable garden, which is in full sun…although some sections are shaded by a tall birch tree during part of the day. First planting was in the area which enjoys part shade through the heat of the day. This siting certainly delayed the komatsuna plants from bolting by a couple of weeks, at least, during the high heat of summer.
We enjoyed the addition of young leaves in our salads so will definitely be growing this variety again in 2018. This time I will be experimenting in seeding a low pot of komatsuna…both green and the new hybrid red variety…to grow on my front porch which enjoys filtered sun.
Posted on February 21, 2018
|Brassica oleracea var. acephala ‘Scarlet Curled’
(BRASS-ih-kah oh-ley-AY-see-ah variety ah-SEF-ah-lah)
Common name: scarlet kale, curly scarlet kale
|Description: An open pollinated, tall, ultra-hardy plant with large, frilly leaves. New leaves are blue-green in colour, maturing to a vibrant deep purple-red. Biennial.
Special Notes: This is a relatively new variety from the UK. As with other kales, ‘Scarlet Curled’ is full of healthy nutrients and anti-cancer properties. But do not limit this one to the vegetable garden! The gorgeous frilled leaves on this cultivar add a delightful splash of sensuous red tones to the ornamental garden. Just be sure to place it where you can still easily harvest a few leaves for the morning smoothie or dinner salad.
How to Grow: Kale prefer humus-rich soil, although they are decently tolerant of almost any soil conditions. Soil acidity is another matter…preferring a pH of 6.5 – 6.8. Targeting this range will greatly benefit the plant’s abilities to draw up necessary nutrients from the soil.
Here in the Pacific Northwest, timing for direct seeding kale in the garden is early March…so as soon as you can work in the garden, work lime into the designated spot in the vegetable garden where kale will be sowed or transplanted. This should be done 2 – 3 weeks prior to seeding.
Soil temperature range for kale seed germination is 10 – 30 °C (50 – 85 °F), but they have been known to germinate at low soil temperatures of 5 °C (41 °F). At the other end of the scale, being a cool season crop, seed germination is very poor at temperatures nearing 35 °C (95 °F).
If you are itching to get growing before March, you can start kale seed indoors under grow lights. I typically start a few kale varieties around mid-February to transplant out in mid- to late March.
Direct sow seeds about a half inch (1.25 cm) deep and space 8 inches (20 cm). Rows should be 24 inches (60 cm) apart. Thin seedlings to a spacing of 18 inches (45 cm). It is possible to transplant the thinned seedlings, if you want lots of kale. This is best done when the plants are at least 8 inches (20 cm) tall and have three or four leaves. Bury the seedlings a little deeper than what they were initially. It won’t hurt the plants.
To harvest, pick 2 – 3 lower leaves from each plant. Do not cut the developing bud in the centre of the plant or you will stop its growth.
For a fall and winter crop of kale, sow seeds in pots or starter trays in mid-July to early August. Sowing in pots or trays allows you to keep the seeds out of the hot sun of high summer. Transplant seedlings into the garden or cool frames when they are tall enough. Be sure to water young seedlings regularly in dry weather. Cover or mulch heavily when fall temperatures threaten to dip to freezing range. This will ensure a harvest of leaves through the winter months.
Pests: Early plantings of vegetables typically come under fire from a number of pests, hungry for a meal. Kale is no different. Cabbageworms, larvae of the small white cabbage butterflies (Pieris rapae) can be a real problem. (For information about this pest, click here.) Covering the young seedlings with floating row cover will help keep the female small whites from laying their eggs on the leaves but be sure to anchor the edges of the fabric securely.
The cabbage aphid, Brevicoryne brassicae, can also be a real pest. Keep a close watch for these as you do not want them to get a foothold on your plants. Because of their incredible reproduction capabilities, one cabbage aphid can produce up to 41 generations in a single season…depending on how long your growing season is. If you see any, hit them with a strong jet of water from the hose to knock them off. Or you can use a soap spray of 1 – 2 teaspoons (5 – 10 ml) dish soap diluted in 4 cups (1 litre) of water. Whichever method you use, be sure to repeat the treatment every 7 days to catch the ones you missed and any new ones which have been born in the meantime.
In our Zone 7a garden: We grew ‘Scarlet Curled’ for the first time this year and were very pleased with its performance, overall health, and taste. However, the jury is still out on its winter-hardy capabilities. Early indications are favourable, though. Two nights of -8.0 °C and -8.5 °C temperatures only caused the leaves to droop very slightly…and lasted only until the temps climbed back to -5 °C and above.
In the kitchen, we really enjoyed the addition of deep-red ‘Scarlet Curled’ leaves to our kale salad. Combined with the dark grey-green leaves of ‘Lacinato’, the blue-green of ‘Dwarf Blue Scotch Curled’, the bright green of ‘Scotch Curled’, and blue-red of ‘Red Russian’ definitely brought the salad to life.
Posted on November 19, 2017