What to plant this week in Whitehorse, YT
With the average last frost date in Whitehorse falling around May 15, gardeners are just entering the window to safely move cold-hardy crops like kale and cabbage from the greenhouse to your raised beds. This week also marks the perfect time for a final push on early harvests of carrots, beets, and swiss chard before our brief summer window tightens.
The next 7 days
Whitehorse, YTGrowing in Whitehorse right now
- The permafrost layer beneath Whitehorse's soil can restrict root depth; ensure all container and in-ground beds have loose, amended topsoil at least 12 inches deep for potatoes and carrots to thrive.
- Our short growing season demands you prioritize high-yield varieties like pole beans over bush types to maximize production before the first frost on September 15.
- Wind exposure is a major factor around the city; use row covers or windbreaks to protect young transplants of tomatoes and peppers from desiccation during sudden gusts.
- Soil tends to dry out rapidly after rain due to low organic matter in many backyards, so apply consistent mulch around lettuce and chard to retain moisture between showers.
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
- Harvest bush beans, pole beans, sweet corn, zucchini, and yellow summer squash before the first frost hits on September 15.
- Protect tender transplants like lettuce and cabbage with row covers if a late spring chill is forecasted after May 15.
- Begin succession sowing carrots and beets now to ensure a steady supply of root vegetables through the growing season.
- Start indoor seedlings for next year's garlic or overwintering crops if your specific microclimate allows.
Pest & disease watch
- Watch for flea beetles chewing holes in young cabbage and kale leaves as temperatures climb above 10°C this week.
- Spider mites can thrive on the drier, wind-exposed microclimates common in Whitehorse neighborhoods; inspect the undersides of Swiss chard leaves daily.
- Late-season slugs may target late-planted lettuce if recent rains have softened the ground surface.
Watering this week
Water deeply but less frequently as soil warms after May 15, allowing plants to establish deep roots before summer heat arrives.
Since frost dates are wide-ranging here, always have row covers on hand for unexpected cold snaps between late April and mid-May.
Whitehorse gardening questions
3Can I transplant my tomatoes now that frost is past?
While the average last frost is May 15, soil temperatures in Whitehorse often stay cool for another week or two; wait until the soil feels warm to the touch before planting tomatoes outdoors to avoid stunted growth.
When should I start harvesting my carrots and beets?
You can begin pulling these root crops now that they are listed for harvest, but keep checking them frequently as our summer is short and bolting or splitting can happen quickly in the heat.
Are there any frost-sensitive flowers I shouldn't plant yet?
Avoid putting out annuals like zinnias or cosmos this week; even though they are on your harvest list for later, they need a solid two-week buffer after May 15 to establish before potential late cold snaps.
Other cities in zone 3a
1See the full zone 3a guide → · Plan your Whitehorse garden in SproutGuide →