Kabocha Squash
Cucurbita maxima
Sow outdoors 2 weeks after your last spring frost. Space plants 36 in (91 cm) apart.
Photo: Theguy002, CC0 · source
When to plant
Timed from your frost dates, so it holds wherever you garden. Give yours and every step below becomes a date.
Optimal Direct Sow
From seedRecommended- Sow outdoors2 weeks after your last spring frost
- First harvestabout 95 days after sowing
Optimal Indoor Start
From seed- Start indoors1 week before your last spring frost
- Begin hardening off1 week after your last spring frost
- Plant out2 weeks after your last spring frost
- First harvestabout 81 days after sowing
Growing kabocha squash
- Spacing in the row
- 36 in (91 cm)
- Between rows
- 60 in (152 cm)
- Planting depth
- 1 inch
- Sun
- Full Sun
- Soil
- Well-drained, rich in organic matter, pH balanced
- Germination
- 5-10 days at 70-95°F
- Harvest season
- Late Summer, Fall
- Mature height
- Vining, 1-2 ft (mound height) / 6-8 ft (trellised)
- Support
- Trellis
- Life cycle
- Annual
Sow seeds 1 inch deep in warm, well-drained soil after all frost danger has passed.
Watering. Consistent moisture, especially during flowering and fruit set. Avoid overhead watering to prevent fungal issues.
Neighbours
The companion chart →Grows well beside
Nasturtium
Radish
Corn
BorageKeep apart from
Potato- Herbs
Feeding
- Seedlings
- Balanced liquid fertilizer (e.g., 5-1-1) after true leaves appear.
- Growing
- High nitrogen initial growth (e.g., 5-1-1), switch to balanced at flowering (e.g., 5-5-5).
- Flowering and fruiting
- High phosphorus and potassium fertilizer (e.g., 2-8-4) once fruits begin to set.
- How often
- Every 2-4 weeks after establishment.
- Note
- Side-dress with well-rotted compost mid-season to support heavy fruit production.
Your kabocha squash, planned to the day.
Canopy turns these timings into dates from your own frost data, places every plant at its spacing on your garden map, and tracks it all the way to harvest.