How to Grow Acorn Squash
Acorn Squash At a Glance
Difficulty
Easy
Category
Vegetable
Sun Exposure
Full Sun
Frost Tolerance
Frost Tender
Cold Hardiness
Survives to 4°C
Plant Family
Cucurbitaceae
Growing Season
Warm Season
Plant Lifecycle
Annual
How to Start It
★ Recommended for beginners
Sow 1 to 2 weeks after your last spring frost, once the soil feels warm. Push 2 to 3 seeds 2.5 cm deep into a small mound of compost-rich soil, and give each mound 90 cm of room. They sprout in 7 to 14 days: keep the strongest seedling and snip off the others at soil level.
Acorn squash is one of the quickest winter squashes, ready in about 85 days, so it suits short summers. The vines sprawl, but the fruit is small enough that you can train the plant up a sturdy trellis to save room.
When To Start
Acorn Squash needs warmth. Wait until your last frost has passed and the soil has warmed before sowing.
We do not have exact sowing dates for this one yet.
When should you plant Acorn Squash?
Your planting dates depend on your local climate. Sign up and add your location to unlock personalized dates.
Your Acorn Squash Planting Window
Start planting
May 15, 2026
Last chance
Sep 10, 2026
Your Acorn Squash Calendar
Set your location to turn these into exact dates and reminders.
Sow acorn squash outdoors now that the soil is warm
1 week after your last frost
Optional: start acorn squash indoors for a head start
3 weeks before your last frost· optional
Pick acorn squash when the skin is dark green and hard
About 85 days after you plant it
Did you water your acorn squash seedlings today? Keep the top of the soil damp until they are up and growing.
About 1 days after you plant it
Lovely to check in on your acorn squash! Water at the base, not the leaves, and give the vines room to spread.
About 42 days after you plant it
Your acorn squash is in the home stretch. Leave the fruit on the vine until the rind is hard and the stem turns corky.
About 71 days after you plant it
Picking time may be here: check your acorn squash.
About 85 days after you plant it
The Journey Ahead
Acorn Squash's Lifecycle
Seedling
Mature Plant
Seed Production
Step 1
Prepare Your Space
2.5 cm
Seeding Depth
90 cm
Plant Spacing
150 cm
Row Spacing
Vertical Growing
Yes: Trellis (support the fruit).
Succession Planting
No.
Good Companions
Bad Companions
Step 2
Planting & Sprouting
Expect sprouts in 7–14 days
Growing Tips
- 1Give acorn squash full sun, at least 6 to 8 hours a day.
- 2Plant it in loose soil with plenty of compost mixed in, since squash is a hungry plant.
- 3Water deeply at the base about once a week, more in hot spells, and keep the leaves dry to slow powdery mildew (a white dust on the leaves).
- 4Feed with a handful of worm castings or a splash of compost tea when the vines start to run and again when the flowers appear.
- 5Late in summer, pinch off new flowers so the plant puts its energy into fruit that can still ripen before frost.
- 6Look under the leaves for squash bugs and their shiny bronze eggs, pick them off by hand, and cover young plants with row cover until they flower.
Seedling Phase
Step 3
Growth & Maturity
~85
Days to Maturity
40 cm
Mature Height
250 cm
Mature Width
Pests to Watch For
Diseases to Watch For
Mature Plant
Step 4
Harvesting
Harvest Window
21 days
When to Pick
Cut when deep green with a hard rind and corky stem; before frost
How to Harvest
- 1Acorn squash is ready about 50 to 55 days after its flower opens, when the skin is dark green and too hard to dent with a fingernail.
- 2The patch that sat on the soil turns from pale yellow to orange when it is ripe.
- 3Cut the squash off with pruners, leaving 2 to 3 cm of stem, and never carry it by the stem.
- 4Bring every squash in before the first fall frost.
- 5Store them in a cool, dry room and eat them within 2 to 3 months, since acorn squash does not keep as long as other winter squash.
- 6Roast the seeds with a little oil and salt for a crunchy snack.
Step 5
Saving Seeds
How to Save Seeds
Acorn squash crosses easily with zucchini, pumpkins and other squash of the same kind, so if any of them flower within about 800 m, the seeds can grow into odd mixed squash. To keep it pure, grow only one of these at a time, or tape a female flower (the one with a tiny squash behind it) shut the evening before it opens, brush it the next morning with pollen from a male acorn squash flower, and tape it shut again. Hybrid F1 seeds will not grow true, so save only from a variety that is not a hybrid. Let the chosen squash sit indoors for 3 to 4 weeks after harvest so the seeds finish ripening, then scoop them out, rinse off the pulp and dry them on a plate for 1 to 2 weeks. Store them in a labelled envelope somewhere cool, dark and dry, where they keep about 5 years.
Seed Production
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