How to grow Kale?
- Latin Family: Brassicaceae
- Latin Genus: Brassica
- Ease of Growing: Easy
- Growing Type: Biennial
Kale grows quite well in warm weather, but so do lots of other potherbs. It really comes into its own in winter, as it can survive temperatures as low as 0 degree F (even lower under mulch). It will continue to produce food when most other crops are just frozen sticks. It can even be gathered from under the snow when frozen solid.
Another benefit of kale is that it can be harvested repeatedly, often sending out new leaves for 6 months or more.
Kale History
This cool season biennial is the most primitive of the Brassica crops and is not very far removed from the wild Brassica oleracea. Kale was once a staple winter food for many Northern European peasants and was especially important during late winter and early spring when it was one of the few fresh foods available. One cultivar was even called Hungry Gap.
Soil Preference
- PH (min/max): 6.0 - 7.5
- PH Ideal (min/max): 6.5 - 7.0
Kale is more tolerant of poor soil than any of the other Brassicas, but the most palatable leaves are produced by rapid uninterrupted growth. For this the soil must be rich and moisture retentive.
It is important that the soil is well drained when growing kale as a winter crop. If the soil is too wet the roots may rot.
Kale likes a [neutral] pH, so add lime if necessary.
How to care for Kale?
Kale is the easiest of the Brassica family to grow (as well as one of the most nutritious and productive) and is extremely productive for the work it requires.
Water
Kale must have plenty of water for maximum productivity and best quality.
Fertilizer
Low nitrogen. Moderate potassium. Moderate phosphorous.
Kale has similar nutritional requirements as cabbage, in that it needs a significant amount of phosphorus and potassium but not a lot of nitrogen.
Early varieties require a higher soil fertility than mid or late-season varieties.
Seeds
Seed Viability: 4-6 Years
Germination Percentage: 75.0
Plants overwintered in the ground will flower the following spring, which gives you a good opportunity to save seed. Kale is usually self-incompatible and must be cross-pollinated by insects. It will cross-pollinate with any other Brassica crop (broccoli, brussels sprout, cabbage, collards), so only one variety should be flowering at one time.
The plants usually produce an abundance of seed and can sometimes get so top heavy they need staking to stop them falling over. The seed is produced in long pods and should be gathered when the older bottom pods begin to split open. Watch them carefully as they shatter easily when they are fully ripe. Cut the entire seed pod bearing stems and dry them in a warm place (I put small quantities in a paper grocery bag, so I don't lose any seeds). The large seeds are easily handled and cleaned. Of course it is essential that they are thoroughly dry before storage.
If you save kale seed (and you should) you will end up with a lot, especially as you should save the seed from at least 5 plants to maintain some genetic variability. This is far more than you will ever need for planting, but you can sprout some of it like alfalfa, or use it to grow micro-greens.
Light
Sun: min. 6 hours daily
Kale will be most productive in full sun, though it will tolerate partial shade.
Conditions:Cold, Cool, Warm
Season:Short Season, Long Season
Storage
The leaves can be frozen for up to 6 months.
Storage Req: Freezer
Storage Temp: 32°F
Storage Length: 0-180 days
Kale can be kept in a plastic bag in the fridge up to 10 days.
Storage Req: Refrigerator
Storage Temp: 35-40°F
Storage Length: 1-10 days
Problems
Aphids
These tiny pests are present on most Brassicas in warm weather. The only time they really disappear is when it gets cold. The simplest way to deal with them is to blast them off the plants with a strong jet of water.
Quail
Quail seem to have a particular affection for Kale and in winter they may strip all of the leaves from the plants. If you are to get any Kale at all in such circumstances you may have to net the plants.
Kale Types
- Siberian
- Scotch
- Portuguese
These varieties are more tender and better flavored than the Scotch Kales. They aren't as hardy, however. Very young leaves can be used raw in salads though they are usually cooked (stems may be tough or not, depending upon circumstances). A biennial, in the spring the flower buds can be used like broccoli.
Kale is a hardy green leafy vegetable harvested in late fall and winter. It develops it best flavor under cool growing conditions. It can also take some light frost allowing it to make it through mild winter weather.
Spring Kale will actually grow right through the summer, but doesn't taste as good when growing at higher temperatures. It is more tender and sweet in cold weather.
In mild climates, kale will continue to grow all winter without disruption and can be harvested continually for months (it will also be in peak condition in the cool weather).
Scotch Kale, Brassica oleracea var acephala, is the most primitive of all the Brassicas and closest to the wild plant. It is famous for its cold tolerance and high nutritional value and was once an important staple food for European peasants.
Kale is a hardy green leafy vegetable harvested in late fall and winter. It develops its best flavor under cool growing conditions. It can also take some light frost allowing it to make it through mild winter weather.
Spring Kale will actually grow right through the summer, but doesn't taste as good when growing at higher temperatures. It is more tender and sweet in cold weather.
In mild climates, kale will continue to grow all winter without disruption and can be harvested continually for months (it will also be in peak condition in the cool weather).
Couve tronchuda, the loose leaf Brassica with the hard to pronounce name, originated in Portugal and is an easily grown and versatile plant. It is commonly known as Portuguese Kale. As a Brassica that doesn’t form a compact head, it resembles collards, but it is different in that it produces thick succulent midribs (costata means ribbed), almost like bok choy. Like the collard it is more tolerant of warm weather than most Brassicas. It is hardy enough to tolerate light frost and this can actually improve its flavor.
Pests
- Cabbageworms
- Cabbage Root Maggot
- Flea Beetle
- Birds
- Thrips
- Aphids
- Cutworms
- Slugs and snails
- Gophers
- Deer
Diseases
- Wirestem
- Clubroot
- Fusarium Wilt
- Damping Off
- Downy Mildew
- Downy Mildew
- Powdery Mildew
- Powdery Mildew
Related Plants
Greens, Juicing
Sprouts
Seacale
Kohlrabi
Collards
Anise
Caraway
Cumin
Cauliflower
Culantro