Vegetables That Do Well Here
Lethbridge has more sun than almost anywhere in Canada, which vegetables love, but a short season, dry air and steady wind that they don’t. Here’s what grows easily, what needs a helping hand, how to pick varieties that will finish in time, and a planting guide built around our frost dates.
On this page
The easy, reliable crops
Start here if you’re new, or if last year’s garden disappointed you. These crops like cool spring weather, shrug off a light frost, and finish well inside our season of about 110 frost-free days. Most go straight into the ground as soon as the soil can be worked.
Roots
Carrots, beets, radishes, turnips and parsnips do very well in Lethbridge. Cool nights make carrots and parsnips sweet, and a fall frost makes them sweeter still. The main job is keeping the seedbed moist until they sprout.
Leafy greens
Lettuce, spinach, Swiss chard and kale. Lettuce and spinach are happiest in spring and again in late summer; chard and kale carry on right through the heat and well into fall.
Peas and beans
Peas go in early, in cool soil. Bush beans wait until the soil warms in late May or early June. Both are generous, quick and fun to pick.
Potatoes and onions
Potatoes are one of the most rewarding crops on the prairies. Onions from sets are nearly foolproof, and garlic planted in fall is ready in late July or early August.
Zucchini and cucumbers
Once the soil is warm in June, zucchini grows almost faster than you can pick it. Cucumbers are easy too, especially grown up a trellis out of the wind.
The cabbage family
Cabbage, broccoli, cauliflower and kohlrabi love our cool nights. Set out hardened-off transplants in mid-May. Watch for small green caterpillars and pick them off by hand.
What it means for you: a first garden of carrots, lettuce, peas, bush beans, potatoes and one zucchini plant will almost certainly succeed in Lethbridge. Add the tricky crops once you know your yard.
Crops that need a helping hand
Heat-loving crops come from places with long, warm nights. Ours cool off quickly, even in July, and the season is short. They can still be grown here, but they need a head start indoors, the warmest spot in the yard, and the right variety.
| Crop | What it needs | How to help it |
|---|---|---|
| Tomatoes | Warm nights, about 60 to 75 days from transplant to first ripe fruit | Start indoors in early April. Plant out late May to early June against a south or west wall. Choose early or “determinate” (bushy) types. Pick green fruit before a hard frost and ripen it indoors. |
| Peppers | Even more heat than tomatoes; they stall below about 10°C at night | Start indoors mid- to late March. Wait until early June to plant. Grow in large dark pots or under a row cover for the first few weeks. Small-fruited and early types ripen most reliably. |
| Melons | Warm soil and a long, hot stretch | Choose small, short-season melons and “icebox” watermelons. Start indoors in early May, plant in early June through black plastic, and keep a row cover on until they flower. |
| Sweet potatoes | About 90 to 100 warm days | A real experiment here. Plant rooted slips in early June into a raised bed covered with black plastic, choose the shortest-season variety you can find, and dig before the first frost. |
| Corn | Warmth (it counts growing degree days above 10°C) | Choose early varieties of about 65 to 80 days. Plant in a block of at least four short rows rather than one long row, so the wind can pollinate it. |
| Winter squash and pumpkins | A long season to ripen and harden the skin | Start indoors in early May, or sow outside in early June. Choose smaller, faster types. Cover on the first frosty September nights. |
Heat-lovers grow on accumulated warmth, not on the calendar. Our page on growing degree days explains how to count it, and why a cool summer can leave tomatoes green on the vine in September.
Choosing varieties for a short, windy season
The variety you choose matters as much as how you grow it. A seed packet tells you most of what you need, if you know where to look.
- Days to maturity. This is the number that matters most. For crops planted out as transplants (tomatoes, peppers, melons), it’s counted from planting out, not from sowing. Look for tomatoes under about 75 days, peppers under about 70, and corn under about 80.
- “Early,” “short season” and northern names. Varieties bred for Manitoba, Saskatchewan, the northern US or northern Europe are good bets. Prairie-bred tomatoes such as ‘Sub-Arctic Plenty’ and ‘Manitoba’, and early ones like ‘Stupice’ and ‘Glacier’, are old favourites for short seasons.
- Bush or compact plants. Bush beans, bush cucumbers, compact zucchini and determinate tomatoes stay low and sturdy. In an open, windy yard they stand up far better than tall vining types.
- Bolt-resistant or slow-bolting greens. Our long June days and hot spells make lettuce and spinach “bolt” (send up a flower stalk and turn bitter). Slow-bolting types last longer.
- Storage varieties of carrots, beets, onions and potatoes keep for months in a cold room. Look for words like “keeper” or “storage” on the packet.
What it means for you: try saving seed from open-pollinated (non-hybrid) beans, peas, lettuce and tomatoes that do well in your yard. Over a few years you end up with plants that suit your own patch of Lethbridge. Seed swaps such as Seedy Saturday are a good place to find locally grown seed (see starting seeds indoors).
Lethbridge vegetable planting guide
These timings are built around our frost dates: about a one-in-three chance of frost after May 25 and before September 11. Tender crops go out around May 25 to June 1, heat-lovers in early June. Indoor start dates match the seed calendar. “Days to harvest” is a typical range; your variety’s packet is the final word.
| Crop | Indoors or direct | When | Spacing | Days to harvest | Notes |
|---|---|---|---|---|---|
| Peas | Direct | As soon as soil can be worked, late April to early May | 5 cm apart, rows 45–60 cm | 55–70 | Hardy. Give them a fence or netting to climb. |
| Spinach | Direct | Late April to early May; again mid-August | 8–10 cm | 40–50 | Bolts in heat and long days, so grow it early and late. |
| Lettuce | Direct | Late April, then every 2–3 weeks to mid-July | Leaf 10 cm; heads 25–30 cm | 30–60 | Afternoon shade in July helps. |
| Radishes | Direct | Late April, then every 2 weeks to May, again from mid-August | 3–5 cm | 25–30 | Go woody and hot in midsummer heat. |
| Carrots | Direct | Late April to early June | 3–5 cm, rows 30 cm | 60–80 | Cover the row with a board or burlap until they sprout. |
| Beets | Direct | Early May to mid-June | 8–10 cm | 50–60 | Each “seed” is a cluster; thin to one plant. |
| Parsnips | Direct | Late April to mid-May | 8–10 cm | 100–120 | Slow to sprout. Sweeter after frost. |
| Swiss chard | Direct | Early to mid-May | 20–30 cm | 50–60 | Pick outer leaves all summer and fall. |
| Kale, turnips | Direct | Early to mid-May | Kale 30–45 cm; turnips 10–15 cm | 40–60 | Both take hard frost. |
| Onions (sets) | Direct | Late April to early May | 8–10 cm | 90–110 (green onions about 30) | Pointy end up, just covered. |
| Onions and leeks (seed) | Indoors | Start late Feb to early March; out early to mid-May | 8–10 cm (leeks 15 cm) | 100–120 from transplant | Best for big storage onions. |
| Potatoes | Direct (seed potatoes) | Early to mid-May | 30 cm, rows 75–90 cm | Early 70–90; main crop 100–120 | Hill as they grow (below). |
| Broccoli, cabbage, cauliflower | Indoors | Start early April; out mid-May | 45–60 cm | 55–80 from transplant | Hardy once hardened off. |
| Bush beans | Direct | Late May to early June, in warm soil | 8–10 cm, rows 45 cm | 50–60 | Rot in cold, wet soil. Don’t rush them. |
| Corn | Direct | Late May to early June | 20–30 cm, in a block of 4+ rows | 65–80 (early types) | Needs warm soil and lots of water at tasselling. |
| Cucumbers | Indoors or direct | Start early May, or sow early June; out early June | 30 cm on a trellis; 90 cm in hills | 50–65 | Cover against wind for the first weeks. |
| Zucchini, summer squash | Indoors or direct | Start early May, or sow early June | 90–120 cm | 45–55 | One or two plants feed a family. |
| Winter squash, pumpkins | Indoors or direct | Start early May, or sow early June | 1.5–2 m | 85–110 | Choose short-season types. |
| Tomatoes | Indoors | Start early April; out late May to early June | 45–60 cm | 55–75 from transplant | Plant deep, up to the first leaves. |
| Peppers, eggplant | Indoors | Start mid- to late March; out early June | 30–45 cm | 60–75 from transplant | Warmest spot in the yard. |
| Melons | Indoors | Start early May; out early June | 60–90 cm | 70–85 from transplant | Black plastic and row cover. |
| Sweet potatoes | Slips | Early June | 30–45 cm | 90–100 | Experimental here; dig before frost. |
| Garlic | Direct, in fall | Late September to mid-October | 15 cm, 5 cm deep | Harvest late July to early August | See garlic. |
Warm days don’t mean warm soil. A hot weekend in mid-May tempts everyone to plant beans, corn and squash. If the soil is still cold, the seed sits and rots. Wait until the soil at planting depth is at least 10°C (beans prefer closer to 15°C), and keep a frost cover handy until early June.
Succession sowing
Sow a whole packet of lettuce on one day and you’ll have forty heads ready in the same week of June, and then none. Succession sowing means planting a little at a time, so the harvest keeps coming.
- Quick crops in small batches: sow a short row of lettuce, radishes or spinach every two to three weeks from late April. Stop the radishes and spinach in late May (they bolt in summer heat), then start again in mid-August for a fall crop.
- Follow one crop with another: when the peas finish in July, pull them and sow bush beans, beets, lettuce or kale in the same spot. Early potatoes and garlic also leave room for a late crop of greens.
- Know your last sowing date: count back from about September 11. Anything that needs 50 days should be in by about mid-July. Hardy greens such as kale and spinach can go a little later, because they keep growing through light frosts.
What it means for you: July is the hardest month for seeds to sprout here, with hot sun and drying wind. Sow a little deeper than in spring, water the row every day until seedlings show, and shade it with a board or a scrap of burlap for the first few days.
Potatoes and hilling
Here’s something to think about while you dig: a potato is not a root. It’s a swollen underground stem, a store of food the plant packs away for next year. The “eyes” are buds, which is why a piece of potato with an eye will grow a whole new plant.
Those tubers form on the buried part of the stem. That’s the reason for hilling: piling soil up around the plant as it grows gives it more buried stem, more room for tubers, and keeps the tubers in the dark.
- Start with certified seed potatoes, not grocery potatoes, which can carry disease and are sometimes treated to stop sprouting. Cut big ones into pieces the size of an egg, each with at least two eyes, and let the cut sides dry for a day or two.
- Plant in early to mid-May about 10 cm deep and 30 cm apart, in rows 75 to 90 cm apart. The tubers in the ground can take cold soil; the leaves can’t take frost.
- First hilling: when the plants are about 15 to 20 cm tall, draw soil up around the stems with a hoe, leaving the top few leaves showing. If a late frost threatens, this also protects the new shoots.
- Hill again two or three weeks later, building a ridge about 20 to 30 cm high. Straw or shredded leaves work too, and help hold moisture in.
- Water deeply and evenly, especially once they flower. Uneven watering in a hot, dry July gives knobby or hollow potatoes.
- Harvest: rob a few “new potatoes” after flowering. For storage, wait until the tops die back, then leave the tubers in the ground another two weeks so the skins toughen. Dig on a dry day.
Green means no. Any potato that has turned green from sunlight contains solanine, which is bitter and mildly toxic. Cut the green parts off, or toss the potato. Good hilling prevents it.
Garlic: the crop you plant in fall
Garlic needs a cold winter. A long spell of cold is what triggers the clove to split into a full head the next summer, which is why fall planting works so well on the prairies.
- Choose hardneck garlic if you can. Hardneck types are generally the hardiest for cold climates, and garlic grown on the prairies is already used to our winters.
- Plant in late September to mid-October, a few weeks before the ground freezes, so the cloves grow roots but not much top.
- Break the heads into cloves just before planting. Plant the biggest ones, pointy end up, about 5 cm deep and 15 cm apart.
- Mulch after the ground freezes with 10 to 15 cm of straw or shredded leaves. This keeps the soil frozen through chinooks, so the cloves aren’t heaved out. Pull most of it back in spring.
- Snap off the curly flower stalks (“scapes”) in late June. The plant puts its energy into the bulb, and the scapes are delicious.
- Harvest in late July or early August when about a third to half of the leaves have turned brown. Dig, don’t pull, and hang to dry in a shady, airy spot for two or three weeks.
Raised beds and growing up, in the wind
Raised beds suit Lethbridge well. They warm up faster in spring, they drain even on heavy clay, and you can fill them with a good mix of soil and compost instead of fighting what’s underneath. The trade-off is that they also dry out faster in our wind and sun.
- Depth: 25 to 30 cm is enough for most vegetables; carrots and parsnips like 30 cm or more.
- Width: about 1.2 m, so you can reach the middle from either side without stepping on the soil.
- Water: mulch the surface, and consider a soaker hose or drip line under the mulch. A raised bed in July may need water every day or two.
- Shelter: a bed set on the east side of a fence or hedge is out of the worst of the prevailing west and southwest wind.
Growing vertically
Peas, pole beans, cucumbers and small squash all climb, and growing them up saves space and keeps fruit clean. In our wind, though, a trellis is also a sail.
- Build it stronger than you think. Steel fence posts driven 45 cm or more into the ground, with livestock panel or heavy wire mesh, will hold. Thin bamboo teepees often won’t.
- Run trellises north to south where possible, so both sides get sun and the plants don’t shade the rest of the bed.
- Tie in vines as they grow with soft strips of cloth. Tendrils alone can’t hold a cucumber vine in a 60 km/h gust.
- Tomatoes: use sturdy cages or stakes put in at planting time, not after the plant is already large.
What it means for you: a strip of snow fence, burlap or shade cloth on stakes along the windy side of the garden cuts wind speed for a good distance behind it. Slowing the wind works better than trying to block it completely. See wind on our growing conditions page.
Harvest and storage
A good Lethbridge garden can keep feeding you into the new year. Different crops want very different storage conditions, and getting them right is the difference between carrots in February and a bag of mush in November.
| Crop | Best storage | Keeps for |
|---|---|---|
| Carrots, beets, parsnips, turnips | Cold and humid: about 0–2°C, packed in damp sand or sawdust, or in perforated bags. Cut tops off, leaving 1–2 cm. | Several months |
| Potatoes | Cool, dark and humid: about 4–7°C. Colder makes them taste sweet; light turns them green. Cure them first for a week or two somewhere dark. | 4–6 months |
| Onions and garlic | Cool and dry, with air moving. Cure them first until the necks are papery. | 3–8 months |
| Winter squash and pumpkins | Cure in a warm, dry spot for about 10 days, then store at roughly 10–15°C, dry. Not in the cold room. | 2–6 months |
| Cabbage | Cold and humid, like roots, but away from them; cabbage smells. | 2–3 months |
| Green tomatoes | Room temperature, out of direct sun, single layer. Check every few days. | A few weeks |
Cold room and root cellar basics
Many older Lethbridge houses have a cold room under the front step. It works because it sits mostly below ground and gets little heat from the house. To use one well:
- Keep a thermometer and a humidity gauge in it. Aim for just above freezing for root crops. If it’s too warm, a small vent to the outside, opened on cold nights, helps.
- Raise produce off the concrete floor on slatted shelves or pallets so air can move.
- Keep apples apart from vegetables. Ripening apples give off ethylene gas, which can make carrots bitter and potatoes sprout.
- Store only your best. Eat bruised, cut or damaged produce first; one rotting potato can spoil a bin.
No cold room? An unheated garage that stays above freezing, a picnic cooler in the garage, or a bin of damp sand in a cool basement corner can all do the job for root crops.
The fastest garden in town. Radishes can go from seed to plate in about 25 days, faster than most library books are due back. Peas and beans make big seeds that small hands can plant easily, and sunflowers can grow taller than a grown-up in one summer.
Wonder: a bean seed is about the size of your fingernail. Where does all the stuff to make a whole bean plant come from? (Hint: most of it comes from the air. Plants build themselves from carbon dioxide, water and sunlight.)
Try this: plant a row of radishes and a row of beans on the same day. Make a chart and measure them once a week with a ruler. Which comes up first? Which do you get to eat first?
Sources
- Environment and Climate Change Canada, Canadian Climate Normals 1981–2010, Lethbridge CDA, frost probabilities.
- Alberta Agriculture, growing degree day information and the Agroclimatic Atlas of Alberta.
- University of Saskatchewan, Gardenline vegetable and fruit growing pages.
- Storage temperatures and planting timings are common horticultural practice for short-season prairie gardens, adjusted to Lethbridge frost dates and the seed calendar on this site.