Crop guide · The goosefoot family (beets, chard, and quinoa relatives)

How to grow spinach

A fast-maturing cool-season leaf crop that delivers harvests in as few as 37 days and tolerates hard frost without protection.

Spinacia oleracea · also called common spinach, garden spinach

Full sun Beginner Frost-hardy
Sun
Full sun
Provide afternoon shade once temps regularly exceed 75 °F (24 °C)
Frost
Hardy
Tolerates hard frost down to about 20 °F (-7 °C)
Spacing
6 in
15 cm between plants
Sow depth
½ in
13 mm
To harvest
37–50 days
counted from sowing
Soil pH
6.5–7.5
slightly acidic to neutral
Timing

When to plant spinach

Windows are counted from the average date of your last spring frost.

Fall planting:6–8 weeks before first fall frost.
Winter planting:in mild climates, sow under cover once daytime temps drop below 50 °F (10 °C).
Too late?Skip a spring sowing once day length exceeds 14 hours or daytime temps regularly top 75 °F (24 °C) — switch to a fall sowing instead.
Background

Why grow spinach

Spinach produces usable leaves faster than almost any other vegetable, fits neatly between other crops in spring and fall, and its flavor sharpens noticeably when grown in cool soil — a quality difficult to replicate with store-bought leaves.

A little history. Native to central and southwestern Asia, spinach is a dioecious annual (plants are either male or female) in the Amaranthaceae family. Long days above roughly 14 hours trigger the shift to flowering, which is why spring sowings bolt faster than fall ones.

The season, step by step

From planting to harvest

Sow outside

4–6 weeks before last frost

Sow seeds ½ inch (13 mm) deep, and aim for 6 inches (15 cm) between plants once thinned. Keep the top half-inch consistently moist until sprouts show; seeds rot if waterlogged, so avoid heavy clay that stays saturated. Seedlings emerge in 5–14 days.

Best soil temp 45–65 °F (7–18 °C) Minimum 35 °F (2 °C) Emerges in 5–14 days

Water and feed

All season

Water deeply every 3–4 days in cool weather; increase to every 2 days if temps climb above 65 °F (18 °C). Water when the top inch of soil feels dry to the touch. Aim for about 1 inch per week including rain.

Side-dress (scatter fertilizer along the row and water in) once when plants reach 3 inches tall; a second application is rarely needed for a 50-day crop. What to use: nitrogen-forward fertilizer such as blood meal or a 10–5-5 organic blend.

Prune and maintain

As it grows

Pinch out the central growing tip immediately if a flower stalk begins to form; this buys a few extra days of leaf harvest before the plant becomes too bitter to use.

Harvest and store

37–50 days from sowing

It's ready when outer leaves are 3–6 inches long, dark green, and fully expanded. Baby leaves are ready at 2–3 inches for salad use. Harvest before any flower stalk (bolt) appears. Cut outer leaves at the base with scissors or snap them off cleanly, leaving the central growing point intact for continued production. For a full harvest, cut the entire plant 1 inch above soil level.

Unwashed, loosely bagged in a perforated plastic bag in the refrigerator crisper drawer; use within 5–7 days. Blanch and freeze for longer storage.

Companions

Good neighbours, bad neighbours

Plant it with

Strawberry

Both want cool soil, steady moisture, and shallow root runs, so spinach can fill the gaps between young strawberry crowns in spring and be cut away well before the berries need the room.

Radish

Radishes often pull flea beetles onto their own leaves and away from spinach; pull and bin the radishes once they size up so the beetles leave with them rather than moving over.

Garden Pea

Peas bank nitrogen in root nodules that is mostly released as those roots break down, so the bed is richer for next season's leafy crop rather than for the spinach growing alongside now.

Garlic

The strong onion smell of garlic foliage can make it harder for aphids to locate spinach by scent. Helpful under light pest pressure, not a substitute for mesh or a water spray once colonies build.

Lettuce

Lettuce shares spinach's cool-season timing, shallow rooting, and 6-inch spacing, so the two interplant cleanly and can be cut over the same few weeks before either shifts to flowering.

Keep it away from

Fennel

Fennel roots release compounds that stunt most garden vegetables, spinach included. Grow it in its own corner or a pot well away from the bed, where its flowers still feed hoverflies and tiny parasitic wasps.

Swiss Chard

Spinach shares the beet family and the same leaf miner and downy mildew problems, so a hard-hit spinach patch often seeds trouble straight into neighbouring chard. Keep them in separate beds where you can.

Good King Henry

Both belong to the goosefoot family and host the same downy mildew and the same leaf-mining flies. A permanent crown grown beside annual spinach carries those problems from one season into the next instead of breaking the cycle.

Quinoa

Spinach shares quinoa's family and its downy mildew and leaf miner pressure; together they give both pests an uninterrupted food supply. Spinach also shades poorly under tall quinoa, so separate plantings suit both.

See spinach in the full companion chart →

Crop rotation

After this crop

Family rest

Give the beet family 2 years away from this spot before any of its relatives return.

Good next crops

The pea and bean family, the tomato family or the onion family thrive in this ground next season.

Spinach is a moderate feeder that leaves little residue and empties the top few inches of nitrogen. Keep the beet family — beets, chard, and spinach itself — out of this ground for 2 years, then follow with peas or beans, the tomato family, or onions and garlic.

Trouble to watch for

Pests and diseases

Pests

Leafminer

Sign
Pale, winding tunnels visible inside the leaf blade; blotchy tan patches on upper leaf surface.
Fix
Remove and bin affected leaves immediately; cover new sowings with fine insect mesh before adults lay eggs.

Aphid

Sign
Clusters of small soft-bodied insects on leaf undersides; leaves may curl or show sticky residue.
Fix
Knock off with a firm water spray; apply insecticidal soap to the undersides of leaves if colonies persist.

Slug

Sign
Ragged holes in leaves, especially near the soil line; silvery slime trails on or near plants.
Fix
Set out iron phosphate bait around the bed at dusk; remove debris where slugs shelter during the day.

Flea beetle

Sign
Numerous small round holes scattered across leaves, giving a shot-hole appearance.
Fix
Cover seedlings with row cover (lightweight fabric tunnel) immediately after sowing; remove weeds at the bed edge.

Diseases

Downy mildew

Sign
Yellow patches on the upper leaf surface with a corresponding grey-purple fuzzy coating on the underside.
Prevent
Space plants at least 6 inches apart for airflow; water at the base rather than overhead; choose resistant varieties labeled with downy mildew resistance codes.

Damping off

Sign
Seedlings collapse at the soil line shortly after emergence; stem appears pinched and water-soaked at the base.
Prevent
Sow into well-draining soil or mix; avoid overwatering in the first two weeks; do not sow into cold, waterlogged ground.

White rust

Sign
Chalky white pustules on the underside of leaves; corresponding pale or yellow spots on the upper surface.
Prevent
Improve air circulation by thinning to final spacing promptly; remove and bin infected leaves; rotate spinach out of the bed each season.
FAQ

Common questions about spinach

When should I plant spinach?
Spring: 4–6 weeks before last frost, as soon as soil can be worked. Fall: 6–8 weeks before first fall frost.
How long until spinach is ready to harvest?
37–50 days, counted from sowing. It's ready when outer leaves are 3–6 inches long, dark green, and fully expanded. Baby leaves are ready at 2–3 inches for salad use. Harvest before any flower stalk (bolt) appears.
Can I grow spinach in a container?
Either works well — needs at least 6 inches of soil depth and good drainage. In containers: 12-inch wide pot, at least 6 inches deep.
How often should I water spinach?
Water deeply every 3–4 days in cool weather; increase to every 2 days if temps climb above 65 °F (18 °C). Water when the top inch of soil feels dry to the touch.
How should I store spinach after harvest?
Unwashed, loosely bagged in a perforated plastic bag in the refrigerator crisper drawer; use within 5–7 days. Blanch and freeze for longer storage.

Verdie turns this guide into your plan

Set your garden's location and every window above becomes a real date — then Verdie reminds you when it's time to sow, transplant, water, and pick.

Download on the App Store
Free to download · iPhone & iPad