What to plant this week in Saskatoon, SK
In Saskatoon, the first week of September marks a critical transition as temperatures drop toward our -35°F winter lows and frost hits by mid-September. While your cold-hardy crops like kale, cabbage, and Swiss chard are ready for harvest, you must urgently bring in heat-sensitive items like tomatoes and squash before night frosts damage them.
The next 7 days
Saskatoon, SKGrowing in Saskatoon right now
- Utilize the remaining warmth of early September to pull out late-sowing tomatoes and yellow summer squash, then mulch heavily to protect overwintering garlic planted recently.
- Take advantage of the cool nights by harvesting collard greens and kale at their peak sweetness; if moving seedlings indoors for spring starts, ensure they are hardened off before May 15 frost risk returns.
- The region's heavy clay soils will retain moisture well during this dry autumn spell, so avoid overwatering lettuce and carrots to prevent rot as the ground cools down.
Sow this week
No direct sowing windows open this week.
Transplant this week
Nothing is due to go out this week.
Harvest soon
38 crops- Bachelor's Button (Cornflower)
- Beet
- Borage
- Bush Bean
- Cabbage
- Calendula
- Carrot
- Cauliflower
- Cherry Tomato
- Chervil
- Cleome (Spider Flower)
- Collard Greens
- Cosmos
- Dill
- Fava (Broad) Bean
- French Marigold
- Garlic
- German Chamomile
- Kale
- Lettuce
- Napa Cabbage
- Onion
- Pansy
- Parsley
- Pole Bean
- Potato
- Scallion (Bunching Onion)
- Scarlet Runner Bean
- Shallot
- Snapdragon
- Sweet Alyssum
- Swiss Chard
- Tomato
- Turnip
- Vinca (Madagascar Periwinkle)
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Continue succession sowing bush beans and pole beans every two weeks to extend your harvest through summer.
- Mulch around young tomatoes and peppers to retain moisture as soil temperatures stabilize after the frost-free date.
- Pinch back the tops of Swiss chard and kale to encourage bushier growth before autumn frosts arrive.
Pest & disease watch
- Watch for late-season aphids on bachelor's button and cosmos stems as plants stress from cooling temperatures.
- Monitor cabbage moths that may still lay eggs on your growing cabbages and cauliflower heads just before harvest.
- Check tomato plants for early blight, a fungal disease common in Saskatoon summers that can spread rapidly with the nightly dew cycle.
Watering this week
Provide deep watering two to three times per week, ensuring consistent moisture for seedlings like dill and chervil.
Harvest zucchini and yellow summer squash when they are small to prevent the plant from going into a dormant phase.
Saskatoon gardening questions
3Can I still sow seeds in my Saskatoon garden this week?
No new sowings are recommended now as the ground is cooling and frost risk has arrived by mid-September. Focus instead on harvesting your current crop of beets, carrots, and turnips before the first hard freezes set in.
How do I protect my overwintering garlic planted this season?
Ensure your garlic is established by now and apply a thick layer of straw or leaf mulch to insulate the bulbs against Saskatoon's severe winter lows. Avoid heavy nitrogen fertilizers at this stage to prevent new growth that could be damaged by frost.
What should I do with my remaining tomato plants before night temperatures drop?
Harvest any ripe cherry tomatoes and yellow summer squash immediately, then cut back the vines of indeterminate varieties to preserve energy for next year. Leave hardy perennials like borage and calendula in place to provide ground cover against the frost.
Other cities in zone 3b
4See the full zone 3b guide → · Plan your Saskatoon garden in SproutGuide →