Fall Spinach Planting: How to Get a Strong Winter Harvest

I’ve learned the hard way that timing is everything with fall spinach. One year, I got busy with other chores, sowed my last bed too late, and watched the seedlings shrivel under an early frost. The next year, I marked the date on the calendar, picked the right variety, and gave them a little protection — we were still picking sweet green leaves in March.

Spinach is one of those rare crops that doesn’t just tolerate the cold — it thrives in it. But to get that strong winter harvest, you need to think ahead. Here’s how I do it.

Timing Your Last Planting for Frost Tolerance

If you want winter spinach, your planting date is your make-or-break decision.

Start by looking up your first expected frost date. In most areas of USDA Zones 4–8, spinach should go in the ground about 6–8 weeks before that date. That gives the plants enough time to germinate and put on solid leaf growth before daylight hours get too short.

In my Zone 5 beds, that means sowing the last round between late August and mid-September. If you’re in a milder Zone 7 or 8, you can push it into October. Colder Zone 4? Aim for late August.

A little trick I use: I sow a first “insurance” bed early, then a second planting two weeks later. This way, one is bound to hit the sweet spot.

Choosing Cold-Hardy Varieties for Overwintering

Not all spinach handles the cold the same way. Thick-leafed, semi-savoy types usually hold up best. My top picks:

• ‘Winter Bloomsdale’ – classic heirloom, rich flavor, curls that shed snow.

• ‘Giant Winter’ – big leaves, slow to bolt in spring.

• ‘Tyee’ – hybrid with strong bolt resistance, good for variable winters.

Look for varieties specifically marked “cold-hardy” or “overwintering” in the seed description. You’ll notice these plants grow slower but hang on longer once the frost hits.

Grandma’s Tip

“If you can feel the chill in the soil at your fingertips, your spinach seed is happier than you are.”

She’s right. Spinach germinates best in soil between 45–68°F. Cooler soil gives you better germination and stronger plants going into winter.

Mulching for Insulation and Soil Protection

Mulch isn’t just about weeds — it’s your first defense against winter kill.

• Use clean straw, shredded leaves, or a thin layer of finished compost.

• Spread 2–3 inches thick once your spinach has 3–4 true leaves.

• Mulch keeps soil temperatures stable, prevents frost heave, and shelters roots from wind burn.

If you mulch too early and heavy, you can slow germination — wait until seedlings are well established.

Low Tunnel and Cold Frame Setups for Deep Winter

If you want to keep harvesting into January (or even February), you’ll need a little help. Two simple setups work wonders:

Low Tunnel

1. Bend ½" PVC pipe over your bed to make hoops every 4–5 feet.

2. Drape with row cover (for mild cold) or clear greenhouse plastic (for deep winter).

3. Secure the sides with sandbags, rocks, or boards.

Cold Frame

1. Build a simple wooden box about 12–18" tall.

2. Top with a salvaged window or clear polycarbonate panel.

3. Face it south for maximum light and open on warmer days to prevent overheating.

Both options trap warmth, block wind, and let you push the season well past your frost date.

Pro Tips – Avoid This Mistake

• Don’t let spinach dry out before frost. Well-watered plants go into winter stronger and bounce back faster in spring.

• Avoid overcrowding. Dense stands trap too much moisture, leading to frost damage and rot.

Picking Leaves Through Late Fall and Early Spring

The cut-and-come-again method is your friend. Snip outer leaves with scissors, leaving the center to keep growing.

In late fall, harvest lightly — just enough for a meal or two a week. In spring, as days warm, your overwintered spinach will explode with growth, and those leaves will be the sweetest you’ve ever tasted.

Your Next Step

Strong winter spinach comes down to three things:

1. Planting at the right time.

2. Choosing the right variety.

3. Giving it enough protection.

Mark your frost date on the calendar, grab your seeds, and start a bed this week. And if you want a simple plan to follow, grab my Fall Spinach Planting & Protection Checklist — it’s printable, covers Zones 4–8, and walks you through every step from sowing to harvest.