Last Updated on September 13, 2026
How Many Spinach Plants per Square Foot?
9 spinach plants per square foot, 4 inches apart in a 3 x 3 grid. Spinach is a cold-soil crop: it germinates at 32°F, stops germinating above 75°F, and bolts once days get long and hot.
The spacing pattern
| Square foot method | 9 per square: a 3 x 3 grid, 4 inches apart |
|---|---|
| 4 x 4 bed (16 squares) | 144 spinach plants |
| 4 x 8 bed (32 squares) | 288 spinach plants |
Spinach is a low rosette that you harvest leaf by leaf, so nine plants per square give you a steady supply from a small area. Because it bolts in early summer, the trick is timing, not spacing: sow it early in spring, again in late summer for fall, and under a cold frame or hoop house for winter.
Planting the square
- Sow as soon as the soil can be worked, one seed at each point of a 3 x 3 grid, half an inch deep.
- Thin to one per spot and pick outer leaves as soon as they are hand-sized.
- Sow again in late August for a fall and winter crop; it holds through hard frost.
Tim’s growing notes
Spinach is one of the 10 crops I direct sow before the last frost, and one of the crops I keep going through winter in the hoop house.
Soil temperature for germination
From my Seed Germination Temperature Chart: spinach germinate from 32°F, do best at 65-75°F, and stop above 75°F.
Days for seedlings to emerge at different soil temperatures, from the same chart:
| Soil temperature | Days to emerge |
|---|---|
| 41°F | 23 days |
| 50°F | 12 days |
| 59°F | 7 days |
| 68°F | 6 days |
When to plant spinach
These are the windows the Plan My Garden planner uses, counted from your average last spring frost. Enter your frost date on the seed starting calendar to turn them into dates. Spinach stops germinating above 75°F, so the sowing window closes at the last frost and reopens in late summer.
| Direct sow | 8 weeks before to 1 week before your last frost |
|---|---|
| Days to maturity | about 40 days |
How I grow them, in brief
Spinach is one of the first seeds I put in the ground: it germinates at 32°F soil and does not care about frost. I sow direct, half an inch deep, nine to a square, and start picking outer leaves as soon as they are hand-sized so the plant keeps producing. The spring crop bolts as soon as the days get long and hot, so I do not fight it; a second sowing in late August gives a fall crop that holds through hard frost, and under the hoop house it keeps going into winter. It is on my list of 10 crops to direct sow before the last frost, and the winter setup is the hoop house.
Where I get seed
Wood Prairie’s organic spinach includes Bloomsdale Long Standing, Winter Bloomsdale and Giant Winter. Code PMG5 takes 5 percent off.
Quick questions
Why did my spinach bolt?
Heat and long days. Spinach sown after mid-spring bolts before it makes much; sow it early, and again for fall.
How many spinach plants in a 4 x 8 bed?
288 at 9 per square, far more than you need at once. Two squares every two weeks in spring is plenty.
Let the planner place them
Plan My Garden is free to start: draw your beds, pick spinach and everything else you want to grow, and it places each plant at the right spacing and gives you a planting schedule for your zip code.
Related: Square Foot Gardening Chart · 10 Crops You Can Direct Sow Before Your Last Frost · Seed Germination Temperature Chart
