Plant of the week: Kale

Kale gets a bad rap.  It’s often pureed into smoothies or roasted into chips–the belief being that it’s too bitter and tough to eat raw.  Many varieties of kale, though, are delicious and tender when picked when the leaves are small.  Kale is easy to grow, especially if you let it go to seed–your garden will be filled with a forest of baby kale plants in no time!

Kale is a good source of phytochemicals, calcium, copper, potassium, and vitamins A, C, and K.  Avoid kale if you are taking blood thinners like Warfarin–the vitamin K can interfere with its effectiveness.

Ideal growing conditions

Kale does best in well-drained soil that is not too rich, so do not mix too much compost in the soil, and use only aged compost.  Kale prefers full sun but will grow in partial shade.

Kale is a cool weather crop, like other brassica crops.  It can survive temperatures of -15C.  It can be grown in the spring and fall; it may bolt and get tough and bitter if the weather gets too hot.  The leaves are sweetest after they’ve been hit by frost.

Start seedlings indoors, 6 weeks before the final frost, or direct sow it outdoors as soon as the soil can be worked.  Set plants about a foot and a half apart.  They take up a lot of room!  You can also grow regular or dwarf varieties of kale in large pots.


  • Curly kale, as the name indicates, has curly leaves and is usually cooked, as it has a bitter or peppery flavour when fully grown.
  • Dinosaur/Lacianto kale has a slightly wrinkled texture.  It is more tender than curly kale, and retains its sweeter flavour when cooked.
  • Red Russian kale (pictured above) has flat leaves that resemble oak leaves.  Its leaves are tender and sweet, which make it suitable for eating raw.  Just make sure to remove the tough stems first

Harvesting, using, and preserving

You can start harvesting kale once it is about 8 inches tall.  Pick the outer leaves when young for use in salads, or wait until they get larger, then pick them for use in cooking.  Leave the centre of the plant untouched so that it can continue to grow.

Kale is usually harvested in the spring and fall, but it’s sweeter in the fall, especially after a light frost.

Use young greens fresh.  Steam, stir-fry, or add mature leaves to sauces and dishes that call for spinach or other cooking greens like chard.

To freeze kale, blanch it as you would spinach, then place in freezer bags.  After you thaw it, you can gently squeeze it to remove excess water (feed the juice to your houseplants!)

To make kale chips: Preheat oven to 400F.  Remove stems, tear kale into bite-sized pieces, arrange on a cookie sheet, then drizzle the pieces with olive oil and a dash of salt.  Bake 10 to 15 minutes.


  • Beets
  • Celery
  • Cucumbers
  • Dill
  • Garlic
  • Lettuce and other greens
  • Mint
  • Onions
  • Potatoes
  • Rosemary
  • Sage


  • Parsley

Fun facts

  • One cup of chopped raw kale contains more than 100% of the recommended daily dose of vitamins A and K, and more calcium than a small carton of milk.
  • Although kale seems like a new fad, it’s been eaten for over 2000 years.  So much for a fad diet food!


Protecting brassicas from cabbage worms

If you are growing cabbage, Brussels sprouts, broccoli, cauliflower, kale, radish, turnip, or rutabaga, you may need to take steps to protect your plants from cabbage worms.  These green caterpillars love to chow down on brassicas and similar plants; after they pupate, they emerge as small, cream-coloured moths (that have a couple of dark spots on their wings).

There are many natural ways to control them, such as attracting their predators into your garden.  One simple solution is to construct a cover made of tulle (a fabric commonly used to make prom dresses and the like).  This fabric mesh allows in rain and sunlight but prevents moths from entering and laying their eggs.

You don’t need to make anything fancy.  You can make a wire hoop frame, or simply set up some stakes that you can drape the fabric over so it does not sit on the plants (as I have done above, on my hail-damaged plants).  Place something heavy on the edges of the fabric, where they rests on the ground.  Or, you can construct something permanent.  There are plenty of ideas on the internet.

For more information on cabbage worms, and other methods of controlling them, see

Bolting isn’t just for horses

Bolting is the process by which plants suddenly stop filling out, and shoot upwards, producing blooms and ultimately going to seed.  Their leaves become tough and bitter and generally inedible.  Bolting is common amongst lettuces and other greens (such as the kale pictured above), cilantro, some members of the cabbage family, beets and other root vegetables.

Bolting is a response to the hours of daylight; plants ‘count’ the hours, then flower when a certain threshold is reached.   It can also occur due to stress–too much heat, not enough water, soil that is too dry or not nutritious enough, fluctuating weather, cold nights and hot days, prolonged cold spells, and any unfavourable growing conditions that encourage plants to bail out and go to seed rather than continue to struggle.

Preventing bolting

  • Choose bolt-resistant or slow-bolt varieties of seeds.
  • Plant lettuces and other greens in successive small batches, pick their outer leaves first, and harvest them when they are young.
  • Sow brassicas and other cold-weather vegetables in mid-summer so that they mature in the cooler fall weather.  Sow them in partial shade, or use shade cloth to protect them from excess sun and heat.
  • Ensure that your soil is nutritionally complete.  Add compost and other supplements as required to provide the nutrients that your plants need.
  • Ensure that your plants get sufficient water, especially in times of extreme dryness.  Mulch plants to help retain moisture.

Anyone else have any other tips?


Direct sowing cool season crops

Once the snow has melted, and the soil is workable (that is, it is neither frozen, cold, or very wet), you may direct sow cool season crops.  These plants tolerate overnight temperatures that hover around the freezing mark, and even a touch of frost; they prefer the cool temperatures of spring and fall rather than the heat of summer, during which they may bolt (go to seed too quickly).

Refer to the seed package to see how many weeks prior to the last frost that you may sow the seeds.  The package may also list an ideal soil temperature.  You may choose to place row covers over the area that you are planting to expedite the warming of the soil and protect your plants from occasional cold nights.

The following plants are quite hardy, and can tolerate a soil temperature of around 5°C:

  • Leeks
  • Peas
  • Radishes
  • Spinach, lettuce, collard greens, kale, kohlrabi, and other greens
  • Sunflowers
  • Turnip and rutabaga

The following plants are also quite hardy, though they prefer a slightly warmer soil temperature of around 10°C:

  • Broccoli (shown above), Brussels sprouts, cauliflower, and cabbage
  • Beets
  • Carrots
  • Chard
  • Kohlrabi
  • Onion sets
  • Potatoes
  • Parsnips

Edible perennials

Most edible garden plants are annuals; that is, they must be planted from seed each year.  Perennials are plants that remain productive year after year.  They may go dormant in the winter, and re-emerge in the spring.

Perennials often need a few seasons to mature before they begin to produce.  Once they are established, they may be prone to spread to the point that they become invasive, so be sure to carefully plan their locations.  It’s a good idea to keep perennials together so that you don’t have to cultivate in and around them each year when you sow your annuals.

Here is a list of edible perennials:

  • Asparagus
  • Bamboo roots
  • Berry bushes, such as raspberries and blueberries
  • Bunching / Welsh onions
  • Chives
  • Collard greens
  • Egyptian onions
  • Fruit trees
  • Globe artichokes
  • Horseradish
  • Jerusalem artichoke / sunchokes (flowers shown above)
  • Kale
  • Lemon balm
  • Lovage
  • Mint
  • Oregano
  • Radicchio (technically a hardy biennial)
  • Rosemary
  • Rhubarb
  • Sage
  • Sorrel
  • Strawberries
  • Wild leeks / ramps

The great zupumpkin!

In one of my first small gardens, I planted a pumpkin plant and a zucchini plant next to each other.  I didn’t save any of their seeds, but the next year, when I spotted a pumpkin plant coming up from the compost, I let it grow.  It started out looking like a bit like an elongated pumpkin or some sort of squash.  Then it ripened to the above specimen, which was christened the zupumpkin.


Cross-pollination occurs when an insect or the wind carries pollen from one variety of plant to another.  The resulting seed, when planted, sprouts a hybrid of its parents.  Since zucchini and pumpkins are both varieties of the same species, they can create the zupumkin (or zumption or pumcchini–your choice) but a cucumber and squash can’t procreate because they’re different species.

Cross-pollination does not affect the current year’s crop, but rather the next year–with one exception: corn.  If the pollen from the tassels of one variety of corn are blown into the silks from another variety, the cob that develops is a hybrid.

Self-pollinating plants

Vegetables like beans, peas, peanuts, eggplant, peppers, lettuce, and tomatoes are self-pollinating. Their seeds will produce plants like the parent, but insects will occasionally cross them, so if you want to be absolutely certain that your seeds will grow true to type, plant each variety at least 10 feet apart.

Insect- and wind-pollinated plants

Vegetables that are pollinated by insects or wind need to be separated by variety, and grown a distance apart (the distance varies with each type of plant).   To ensure that your seeds grow true to type, grow one variety of each type, or separate the different varieties.

Vegetables that willingly cross-breed

The following plants or plant families are prone to cross-pollination.  If you are planting them with the intention of keeping their seeds, keep varieties well separated.

  • Beets and Swiss chard
  • Cauliflower, cabbage, kale, Brussels sprouts, kale, collard greens, and broccoli
  • Corn
  • Cucumbers
  • Honeydew, cantaloupe, and other melons, excluding watermelons
  • Peppers (hot and sweet)
  • Squash (some varieties)
  • Zucchini and pumpkins

From the side dish to the main course

Recent studies have shown that the ideal diet is one that is rich in vegetables and fruits.  The benefits to our health increase if we go beyond the traditional options, such as carrots, potatoes, and beans, and eat a wide variety of vegetables and fruits.  No one plant contains all of the nutrients we need, so it’s best to mix it up, and enjoy a rainbow of colours, textures, and types.

Health benefits

The benefits are widespread:

A diet rich in vegetables and fruits can lower blood pressure, reduce risk of heart disease and stroke, prevent some types of cancer, lower risk of eye and digestive problems, and have a positive effect upon blood sugar which can help keep appetite in check. (source)

There is a growing body of evidence suggesting that dietary patterns emphasizing fruits and vegetables may be linked to better psychological health.[i] A recent study found that higher fruit and vegetable consumption may increase well-being, curiosity and creativity, possibly related to micronutrients and carbohydrate composition.[ii] This is probably related to the fact you are giving your body and brain more healthy vitamins, minerals, phytochemicals and fiber. (source)

Meatless Monday

The Meatless Monday campaign, which started in 2003, encourages participants to abstain from meat on Mondays as a way to improve their health and that of the planet.  Why not expand this campaign to your garden, and try to grow a favourite vegetable, or something new, and use it as a centrepiece for your Monday meals?

Fun vegetables to grow

Here are some suggestions for interesting and healthy vegetables to try:

  • Rainbow chard is rich in vitamins.  There are many ways to cook it, or you can enjoy it in salads.  You can use it as a replacement for recipes that call for cooked spinach.
  • Sweet potatoes are extremely high in vitamin A and rich in fibre.  They are delicious baked and in soups.
  • Beets are versatile.  You can eat the greens or the beetroots themselves, or grate them and add them to cake.  They come in a variety of colours, like red, gold, and white.  They’re high in folates, iron, and other minerals.
  • Kale, like most green vegetables, is high in iron.  It likes the cold weather and doesn’t mind a little snow.
  • Eggplants/aubergines are often used as replacements for meat.  There are several varieties to choose from.
  • Winter squash are great in soups, casseroles, or as side dishes.  You can grow them in many colours and unusual shapes.
  • Ground cherries taste like a combination between pineapples and strawberries.  They can be eaten fresh or used in preserves, pies, and other sweet treats.

More resources

Information on plant-based proteins.