Smart Tips for Growing Kale

Growing Kale: Leaves of kale in a garden, with text "Growing: Kale" and the Smart Gardener logoKale is a hearty, nutritious plant that is easy to grow and perfect for every garden.

There’s a reason kale is so popular with the health food crowd: It’s chock full of nutrients. Whether you’re putting it in smoothies, making chips, cooking it in stews or massaging it salads, the uses for kale are nearly endless.

But did you know it’s also one of the easiest plants to grow? And kale fresh from the garden is crispy and sweet and will win over even the pickiest of eaters.

Growing Kale: curly kale leaves on a brown and white gingham tea towelKale is considered closer to wild cabbage than most of the other domesticated forms of Brassica oleracea. There are three basic types of kale, with slightly different growing requirements, so finding one that’s perfect your garden is easy!

Below you’ll find our smart tips and advice on growing kale.

Portuguese Kale
This loose leaf variety, Couve tronchuda, originated in Portugal and is almost more like collards (another Brassica) in appearance as well as being more tolerant of warmer temperatures than other varieties. Tender with thick succulent midribs, Tronchuda Beira is milder and sweeter than other Brassicas (broccoli, cabbage, cauliflower, collards, etc.).

Scotch Kale
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. Lacinato (also known as dinosaur kale for its bumpy texture) is a stunning garden plant as well.

Siberian Kale
Siberian kale varieties are more tender and better flavored than the Scotch kales. They aren’t as hardy, however. Red Russian is a delicious heirloom variety with attractive red stems, and very young leaves can be used raw in salads.

Tips for Growing Delicious and Hearty Kale

Soil Preparation
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. Kale likes organic matter, so amend the soil by digging in 2″ of compost or aged manure. It also performs best in soil with a neutral pH, so add lime if necessary.

Plant Care
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 a little work. Its large leaves can lose a lot of water in warm weather, so be sure water the plants regularly and thoroughly for maximum production and best quality.

Once it is established, kale is pretty independent. You only really need to worry about weeds while it is young. Start harvest thinnings when all the seedlings have emerged, and gradually thin them to the recommended spacing to give each plant enough room to spread out. Use a mulch in summer to suppress weeds, keep the soil cool and conserve soil moisture.

Growing Kale: purple/red curly kale in a gardenPlant Protection
In warm weather, aphids are one of the most common pests on most Brassicas. You can spray plants with a soapy mixture, but honestly the simplest way to deal with them is to blast them off the plants with a strong jet of water.

Downy mildew can also affect kale, especially in humid areas, appearing on the underside of leaves. You can control it by improving air circulation and keeping the leaves dry when watering. If you must use overhead sprinklers, then water in the morning or early evening, so plants don’t stay wet all night. Spores overwinter on crop debris, so clean up the beds between crops, and rotate plants seasonally.

As for other pests, there are several types of caterpillars that live only on Brassicas. Many of these can strip a young plant almost overnight. Additionally, some birds, especially quail, seem to have a particular affection for kale. In winter they will eat all of the leaves. In both cases you may have to place nets over the plants to get a decent harvest.

Pollination and Seed Saving
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, cabbage, cauliflower, etc.), so only one variety should be flowering at one time.

The plants 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.

If you save kale seed (and you should!) you will end up with a lot. Since you need seed from at least 5 plants to maintain genetic variability, and each plant makes thousands of seeds, you will have far more than you will ever need for planting. Fortunately, you can sprout some of it like alfalfa, or use it to grow micro-greens.

Alternative Growing Options

Growing Kale: Portuguese kale plants in the garden, covered with frostCover crop
Kale is sometimes planted as a green manure or winter cover crop. In areas with mild winters it will produce a lot of foliage over the winter with the bonus that you can eat it! In spring the flower buds can be eaten like broccoli before incorporating the plants into the soil.

Ornamental use
Some kale varieties have very attractive foliage and would be at home in the flower garden. The specially-bred ornamental kales are technically edible, but they are more beautiful than they are tasty.

Winter garden
In mild climates, you can grow kale in a winter garden. In areas with hard freezes, though, it will need some protection. It can be grown in a greenhouse or cold frame, and can even be grown as a houseplant.


Smart Gardener makes it easy to start a garden. We can help you decide which type of kale will work best in your garden and give you the advice you need to get started, and then send you weekly to-dos to keep you on track!

Smart Gardener Tips for Growing Kale

Extending your summer garden growing season is surprisingly easy. With a little planning you can continue to harvest tender plants like lettuces and tomatoes for several weeks, and maybe longer.

Extending Your Summer Garden Growing Season

It might be difficult to imagine it right now, but the warm days of summer won’t last. But don’t worry! Extending your summer garden growing season is surprisingly easy. With a little planning you can continue to harvest tender plants like lettuces and tomatoes for several weeks, and maybe longer.

Early Frost Protection

The simplest season-extending technique is to protect the tender crops from the first occasional fall frosts. A sudden dip in temperature will do a lot more damage to plants than a gradual decline (which gradually hardens them off).

Extending Your Summer Garden image garden bed with a plastic row cover

Especially frustrating to gardeners is the fact that these early frosty nights are almost always followed by several weeks of good growing weather. The good news is that the simple act of covering your tender plants for a night or two may reward you with several more weeks of harvests.

Happily you can get advance warning of an oncoming frost and act to protect your plants. Almost anything will give protection from a light frost. The point is to cover the plant and create a small air space that will stay warmer than the cold air.

•    old blankets
•    plastic sheeting
•    row covers
•    straw mulch
•    cloches
•    cold frames

Draping old blankets or plastic sheeting is the most common way you see gardeners protecting their tender plants from a frost. Row covers using plastic sheeting and arches that are attached to the garden bed, are a somewhat more long-term solution. Just be sure to open it up from time to time to release excess moisture.

Another option is to put down a layer of straw mulch. You just make sure you put down several inches to make sure they’re covered. This has the added benefit of helping to protect the soil from erosion from heavy winter rains.

Severe Frost Protection

Cold frames and cloches can even protect plants from more severe frosts. Plastic or glass cloches can be purchased at your garden center, or you can make your own. Common household items and plastic packaging you’d otherwise put in the recycle bin are great cloches. Milk jugs with the bottoms cut out or clear plastic take-out containers. Just make sure you stake them to the ground so they don’t blow away!

A cold frame is a bit more elaborate, but it will give you more room for growing. They look like a miniature greenhouse, and are generally constructed as a small box with glass or heavy-duty plastic windows. You can build them to fit your needs, making them ideal for taller plants such as tomatoes. Once you remove the stakes, your tomato plants can be laid down on the ground for easier protection.

How Long Can You Extend?

Extending Your Summer Garden image lettuces in a cold frame

Extending your summer garden growing season is a great idea, but for how long? Realistically, you should only try to protect your tender crops for as long as there is good growth in the daytime. It isn’t worth protecting them once the days get too cold and the sunlight hours get short, as they won’t thrive.

At that point, it is better to replace them with hardy winter crops. Or you can decide to take a break for a month or two and hibernate, and enjoy your well-earned rest. If you’ve been diligent and canned, dried, or frozen some of your earlier harvests, you can enjoy the fruits of your own labor until you’re ready to start preparing again for next year’s spring garden.

Planning a winter vegetable garden is surprisingly easy. Follow these tips to keep growing your own vegetables once the summer crops are done.

Planning a Winter Vegetable Garden

As the days grow shorter and the temperatures start to drop, many gardeners move indoors for the winter. But for those of us who live in a mild climate where we can grow late fall and winter crops, we can keep right on growing as long as we pick the right crops, get them in the ground early enough and provide them with the proper protection. Follow these tips to start planning a winter vegetable garden to keep growing once the summer crops are done.

What to Grow

Some cool weather crops are much better suited to growing in fall than in spring. Often by the time it’s warm enough for plants to mature in spring, longer days will cause short-day crops (spinach and oriental cabbage) to bolt. The warm temperatures adversely affect their flavor as well.

But if you plant these crops in late summer, they’ll get a good kickstart in the warmth of a late-summer sun, and then mature more slowly in the shorter, colder days that follow.

Planning a Winter Garden image close up of a broccoli head and green leavesWhen planning a winter vegetable garden, these tried and true hardy crops are your best bet:

•    Broccoli
•    Brussels Sprouts
•    Cabbage
•    Carrot
•    Cauliflower
•    Chard
•    Horseradish
•    Jerusalem Artichoke
•    Kale
•    Leek
•    Mâche
•    Mustard Greens
•    Parsnip
•    Turnips

Even within these crops, it is important to use the right variety at this time of year, as hardiness can vary considerably. Fortunately, for every plant in the Smart Gardener database we’ve included a ‘Growing Conditions’ tag in the plant profile so you can easily see what each plants needs—cold, cool, warm or hot weather. For fall and winter crops, you want to look for plants that can tolerate cold weather.

When to Plant

Fall and mild winter crops commonly take longer to mature because the sun is weaker and the days are shorter. The best way to determine the right time to plant a fall crop is to figure out the number of days it takes for it to reach maturation (adding extra days to allow for slower growth in fall). Determine the day you want them to mature (in areas with frost, this is normally just before the weather turns too cold for good growth). Subtract the number of growing days from the maturation date and you have the sowing date.

It’s a good idea to plant a few successions at this time to make sure you get at least one crop before the frosts and possibly more if the frost is later than expected. If you rarely have frosts, you may be able to continue growing these crops through the winter.

planning a winter vegetable garden image of a cabbage plant with frost on the leavesWhere to Plant

Beds for winter crops should receive all of the sunlight they can get, so make sure they won’t be shaded. A south-facing slope is the best choice as it gets extra heat from the sun. You can even shape your shape winter beds so they tilt slightly to the south to give them a little extra solar gain.

The beds themselves should be well protected from cold winds. Don’t plant the winter garden in a low-lying area, as it might be a frost pocket and much colder than a more elevated slope.

The soil should also be well drained, as dampness is often as great as enemy of winter plants as cold is (much of the value of cloches and cold frames is due to their protecting plants from moisture).

Let Smart Gardener Help

The easiest way to plan a fall and winter garden is to let Smart Gardener do the work for you. If you already have a spring/summer garden, you can create a copy of your existing layout and select fall/winter, and then select the plants you want to grow.

Based on your frost dates, Smart Gardener will help you find which varieties are best for your climate, and let you know when it’s time to plant them.

Sugar Snap Peas

Have you considered growing peas? Looking for something to feed your sweet tooth, straight from the garden? Look no further than the Sugar Snap pea. There’s a reason they’re called “garden candy.”

The Sugar Snap is actually a relative newcomer to the garden (first introduced in 1979), but it is now established as one of the great treats of spring. When my Sugar Snaps start to ripen they become the center of the garden and remain so until all the pods are gone.

The Sugar Snap differs from traditional garden peas (like Green Arrow) in that the whole pod is edible, and differs from the edible podded snow peas (like Mammoth Melting) in that the pod is fat, sweet and delicious.

As the whole pod is edible they produce a significantly bigger harvest and don’t need shelling. The original Sugar Snap variety was so successful it eventually spawned a whole range of snap peas: bush varieties, disease resistant types and some without strings. There are now even yellow, purple and pink tinted types.

The Sugar Snap was hailed as a revolutionary new kind of pea when it appeared, but it wasn’t actually as new as it seemed at the time. It turns out that the Amish have been growing snap peas for a long time and they are so similar that a casual observer probably wouldn’t be able to tell the difference.

Should I grow peas?
Peas (along with beans) have a special place in the vegetable garden because they are host to nitrogen fixing bacteria and so can add fertility to the soil as they grow. This won’t happen unless the right type of bacteria is present in the soil though, so if you haven’t grown peas within the last five years you should inoculate the seed with a suitable strain of inoculant.

The real flavor of Snap peas comes through best when they are eaten raw and this is how almost all of ours get eaten. My children will eat them straight from the vine all day long and few pods actually make it as far as the kitchen (their friends have been known to strip a planting of all pods of any significant size). They are also good when very lightly steamed, but don’t cook them for more than a couple of minutes, or they may turn to mush.

Tips on growing great peas
Air Temperature: Peas thrive in cool weather and don’t like heat, with 60-75˚ F being optimal. They are fully hardy and the first planting can be sown directly into the garden in early spring, a month before the last frost date.

Soil Temperature: The soil doesn’t even have to be very warm, as they will germinate (if rather slowly) at temperatures as low as 40˚ F.

Succession Planting: It is a good idea to make several succession plantings about 3 weeks apart, to ensure an abundant supply of pods until the weather gets too warm.

Weeding: The established plants don’t require much care. Weeds can be a problem for the young seedlings, but they soon outgrow and overshadow any weeds.

Watering: They do need regular moisture, but in early spring there is usually plenty in the soil and you rarely need to water.

Getting set up
The original Sugar Snap is a pole variety and must have a tall support structure for good growth (hog wire fence works well). If it isn’t tall enough they will eventually run out of climbing room and flop over (when my dad first grew them in England they went right over the top of his 6 foot high wall and started supplying his neighbor with pods).

It is a good idea to set up your supports before you plant, as it’s easy to damage the fragile seedlings. If you don’t want to deal with such a tall plant there are now bush varieties, such as Sugar Ann.

It is easier to provide support for the plants when they are growing in rows, so they are commonly planted in double offset rows with 3” between the plants and 6” between the rows. If you need more than one double row, then leave 24” between the pairs of rows.

You can also wrap hog wire fence into a cylinder and plant in a circle around it (this looks quite ornamental when fully covered, though not for long).

Established plants grow vigorously and quickly produce a wall of foliage 6 to 8 feet high, which makes an attractive (though temporary) screen.

Pests to watch out for
The biggest obstacle to growing Snap Peas is getting them established. It’s not that they are hard to germinate (this is easy) but rather that birds like to eat the succulent green parts and often pull the emerging seedlings out of the ground. The best way to prevent this is to cover the whole bed with netting.

Mice can sometimes be a problem too, as they sometimes dig and eat the seed before it has even germinated. If they are a problem you might have to start your plants indoors, though they dislike transplanting, so must be grown in individual cell packs (and not kept indoors for too long).

Ready to harvest!
The pods mature quickly after pollination and you need to check and harvest the plants regularly (every day or so). Harvest the pods when they are fat and round and sweet to taste. Don’t harvest too early or they won’t be as good as they can be.

It is important to pick all of the pods as they size up, if you leave some on the vine the seed will mature and production may decline (if this happens save the seed for planting next year). In cool weather, a well managed planting may yield for 6 weeks or more, though if the weather turns hot it may be as short as 2 weeks.


Smart Gardener makes it easy to grow peas, and more! We help you every step of the way from selecting seeds and preparing your garden, to sending you weekly reminders of garden tasks to keep your plants healthy and happy!

Peas for St. Patrick’s Day

Image: Peasl Photo source: Jessica Ruscello, UnsplashIn Ireland, St. Patrick’s Day is the traditional day to plant peas in a spring garden. In the United States the timing can vary somewhat from zone to zone, but March 17th still works well as a guide for starting peas for most areas. And what a perfect way to bring your garden a bit of the “luck of the Irish” by planting something green!

Why you should grow peas.

Did you know peas have been cultivated by humans for anywhere from 8,000 to 12,000 years? Peas are an easy, rewarding crop for spring, and are a great way to fix nitrogen in the soil for your summer plants. As an early spring crop they can be out of the ground by June, leaving time for a warm weather crop to succeed them.

Selecting a variety.

Image of peas in a basket

Dried Shelling Peas are typically used for soups or stews, and fresh shelled immature peas are good lightly steamed or boiled. Their pod is too fibrous to be edible, and the peas themselves must be removed from the shells, hence their name. Bush Shelling peas grow in a compact bush form, while the more common Vine Shelling peas, which grow on vines that require staking or trellising but which are generally more productive than bush varieties.

Snap Peas are a more recently developed edible-podded pea, this one originated in America. The pod is thicker and more succulent than that of the Snow Pea, and less fibrous than standard Shelling Peas. These are now one of the most popular types of pea, because there is no work in shelling and very little waste.

Snow Peas have thin crisp pods that are nearly translucent and bright green, with tiny seeds. The whole pod is edible and quite sweet when picked at the right time. The name may come from the whitish tint reflected from the pods, or because of their tendency to grow at the end of winter, just before the last spring freeze. As their name suggests, they can be covered with snow during these times, but still keep growing.

When to plant.

In moderate climates, you can sow directly into your garden bed, while in colder climates you may need to start them indoors. Fortunately, peas do well in containers, so you may not even need to transplant them!

In warmer climates, you may have already started your peas back in January or February, but you can still continue to sow new seeds for a second harvest before the warm days of summer.

Getting started.

The best soil for peas is a loose well-drained loam. Peas don’t need a lot of nitrogen, as they can obtain their own. In fact, if nitrogen is too easily available they won’t bother to fix any. Peas do need phosphorus (colloidal phosphate) and potassium (wood ashes), as well as calcium and magnesium (use dolomitic limestone).

If the soil is compacted double digging is beneficial. If it is poorly drained, use raised beds, especially for early plantings, as they don’t like wet soil. In very poor soils it may pay to plant your peas in trenches, filled with a mixture of soil and compost.

If you’re growing a vining variety, you will need to supply a trellis or poles for the plants to grow along.

Spring Vegetables

Image of seedlings in pots. Photo Source: Francesco Gallarotti, UnsplashSo you’ve got your soil ready, it’s finally warm enough, and now you’re thinking about what to plant. It’s tempting to start planting all those great seeds you bought over the winter, but it’s best to take a moment and consider what weather conditions each plant needs to germinate and thrive. Each plant has an appropriate time to be planted, and it’s important to be aware of which plants can go out at what time.

The vegetables that grow well in spring all originated in temperate climates and prefer cool (50-75˚ F) growing conditions. When you first plant your spring crops, the soil and air are cool and days are fairly short, so crops germinate and grow slowly. As spring progresses the days lengthen and the weather gradually warms, until by the time most crops are ready to harvest it may be warm most of the time. Fall has cool weather too, but there the reverse is true, conditions are warm for seed germination and growth (and pest activity), while maturation takes place in cooler weather.

When to plant
Blue spade in garden bed. Photo source: Markus Spiske, UnsplashIt is important to get your spring crops into the ground as early as possible, so they have enough time to grow and mature before the long, warm days of early summer cause them to bolt or develop bitter or pungent flavors. Fortunately cool weather crops aren’t perturbed by minor cold snaps, so planting them early isn’t a big problem. If it is cold they will just sit and wait until the weather warms up enough for growth.

The hardiest crops can be planted as soon as the ground is suitable for making beds in spring, which may be 4 to 8 weeks before the last frost date. These plants include: leek, onion, parsley, pea, spinach, and shallot.

The slightly less hardy crops can be sown 2 to 4 weeks before the last frost date. These include: lettuce, cilantro, mustard, and radish.

The rest of the spring crops are sown a couple of weeks before last frost date. These include: beet, carrot, broccoli, cabbage, chard, kale, and potato.

 

Smart Gardener makes it easy
We show you quickly and easily when it’s the right time to start your seeds indoors or outdoors, based on your region. Just check the Overview tab in the variety descriptions, and you’ll see when to start your seeds, transplant your starts, and harvest your vegetables. The top lines are for spring/summer crops, and the bottom lines are for fall/winter. Easy as can be!

Planting Overview showing sowing guide