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What to plant this week in Kingston, ON

Week of 2026-W37

Kingston gardeners are officially in the thick of summer warmth as frost dates average May 1, making this your final sprint before late-season cold snaps around October 15. With our humid continental climate and clay-heavy soils common along the St. Lawrence banks, focus entirely on harvesting those summer crops that are ready right now.

The next 7 days

Kingston, ON
Today
9/12
76° 49° 💧23%
Sun
9/13
79° 64° 💧31%
Mon
9/14
68° 51°
Tue
9/15
69° 56°
Wed
9/16
75° 64° 💧22%
Thu
9/17
70° 55° 💧40%
Fri
9/18
63° 54° 💧28%
Avg high 72°F Rain total 0.8" Humidity 73% Wind 9 mph
On the ground

Growing in Kingston right now

  • Target immediate harvests for Bush Beans, Cucumbers, Zucchini, and Summer Squash while humidity peaks to prevent rotting before the first frost in mid-October.
  • Our heavy clay soils retain moisture well but drain slowly; ensure good airflow around late-planted Tomatoes or Peppers to mitigate fungal issues common in Kingston's humid summers.
  • Take advantage of the mild October window (avg. 1st frost: Oct 15) to plant hardy overwintering crops like Garlic and Leeks now for a spring harvest next year.
In the ground

Sow this week

No direct sowing windows open this week.

Move out

Transplant this week

Nothing is due to go out this week.

Coming ripe

Harvest soon

42 crops
  • Basil
  • Borage
  • Bush Bean
  • Cantaloupe
  • Celery
  • Cleome (Spider Flower)
  • Cosmos
  • Cowpea (Black-Eyed Pea)
  • Cucumber
  • Dahlia
  • Edamame
  • Fennel
  • Flour Corn
  • French Marigold
  • Garden Verbena
  • Garlic
  • Ghost Pepper (Bhut Jolokia)
  • Gourd (Ornamental/Bottle)
  • Honeydew Melon
  • Leek
  • Lima Bean
  • Lisianthus (Prairie Gentian)
  • Loofah (Luffa)
  • Nasturtium
  • Ornamental Sweet Potato Vine
  • Parsnip
  • Pole Bean
  • Potato
  • Pumpkin
  • Roselle (Cranberry Hibiscus)
  • Scarlet Runner Bean
  • Shiso (Japanese Basil)
  • Summer Savory
  • Sunflower
  • Sweet Corn
  • Thai Basil
  • Vinca (Madagascar Periwinkle)
  • Watermelon
  • Winter Squash
  • Yellow Summer Squash
  • Zinnia
  • Zucchini
Do this now

Seasonal tips

  • Mulch around transplanted squash and melons to retain moisture as summer heat builds up.
  • Succession sow pole beans or sweet corn every two weeks for a continuous harvest throughout July.
  • Pinch back tips on basil, celery, and marigolds to encourage bushier growth before the end of the season.
Keep watch

Pest & disease watch

  • Monitor Zucchini and Squash plants closely for squash bugs, which thrive in Kingston's humidity and can rapidly defoliate late-summer crops.
  • Watch for aphid colonies on the new growth of Basil, Shiso, and Thai Basil due to the warm, stagnant air pockets often found near our river valleys.
  • Check for powdery mildew on Zinnias and Sunflowers, a common issue when our local summer rainfall comes in heavy bursts without adequate plant spacing.
Water

Watering this week

Water deeply at soil level in the morning to keep roots cool and reduce evaporation during hot days.

One more thing

Harvest zucchini and yellow summer squash early in the day when they are most tender and flavorful.

Asked locally

Kingston gardening questions

3
When should I stop planting cool-season crops like Garlic or Leeks?

You can safely transplant Garlic and Leeks now because the ground remains workable until early spring, but remember they need to establish roots before our first frost around October 15. Plant them in well-drained spots away from low-lying clay pockets that freeze too quickly.

How do I extend my harvest of Bush Beans and Pole Beans into late September?

Harvest your Bush Beans frequently every few days to signal the plant to keep producing, while supporting your Pole Beans with sturdy trellises to withstand Kingston's frequent summer wind gusts near the water.

What should I do if my Zucchini starts getting soft spots before frost?

Remove any rotting fruit immediately to stop the spread of soft rot bacteria in our damp climate, and try to harvest all remaining marketable squash by mid-October before temperatures drop below freezing.

Nearby

Other cities in zone 5b

8

See the full zone 5b guide → · Plan your Kingston garden in SproutGuide →