Spinach
Spinacia oleracea
Quick and productive in spring and autumn, and almost impossible to keep going through midsummer — spinach bolts in response to long days as much as to heat, so a June sowing runs to seed however carefully it is watered. Grown in its two proper seasons it is one of the most efficient crops per square metre in this catalogue.
- Position
- Full sun or Partial shade
- Water
- moderate demand
- Drainage
- Moisture-retentive
- Grows to
- 20–30 cm × 20 cm
- Hardiness
- H5
- Harvest
- May to April
- Difficulty
- Some care needed
Described view
A dense stand of young spinach with smooth dark green leaves on red-tinged stalks, several outer leaves already picked
August
Sow outdoors
Coming next month: harvest.
Spinach’s year
Resolved for United Kingdom (general). Every window is stored against a climate event rather than a date, so a late frost pocket runs later than the band shows. What else August calls for.
| Activity | J | F | M | A | M | J | J | A | S | O | N | D |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sow outdoors | March. | April. | May. | August. | September. | |||||||
| Harvest | March. | April. | May. | June. | September. | October. | November. |
Names that cause confusion
perpetual spinach — Not spinach at all, but a leaf beet — a cultivar group of Beta vulgaris, the same species as beetroot and chard. It does not bolt the way true spinach does, which is precisely why it is often grown instead.
New Zealand spinach — Tetragonia tetragonioides, an unrelated plant used as a hot-weather substitute because it does not bolt.
Timing that travels
The band above resolves this plant's windows into months for one region. These are the windows themselves, stored against a climate event rather than a date — which is the form that survives being carried to a colder garden, a frost pocket, or next year.
- Sow outdoors0–8 weeks after the soil becoming workable, every three weeks through spring
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Spinach — sowing
Checked 2026-08-13
Spring sowings. Stop by late May: anything sown into lengthening days bolts.
- Sow outdoors4–10 weeks before your first autumn frost
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Spinach — autumn sowing
Checked 2026-08-13
Autumn sowings, for a late crop and for overwintering under a cloche.
Conditions it needs
- Light
- Full sun, Partial shade
- Direct sun
- 4 hours a day or more
- Frost
- Hardy
- Hardiness rating
- H5 (RHS)
- Grows best at
- 10–20 °C
- Germinates at
- 4–24 °C
- Soil
- Loam, Peat-free compost, Silt
- Soil pH
- 6.5–7.5
- Drainage
- Moisture-retentive
- Water needs
- moderate
- Drought
- poor tolerance
- Waterlogging
- poor tolerance
- Heat
- poor toleranceSourced guidanceDepends on conditions
- Wind and exposure
- good tolerance
Where these figures come from
- LightSourced guidancehigh confidence
Partial shade helps in late spring, when it delays bolting a little.
- Royal Horticultural Society: Grow your own: spinach
Checked 2026-08-13
- Direct sunHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- FrostSourced guidancehigh confidence
Autumn-sown spinach overwinters under a cloche and crops early the following spring.
- Royal Horticultural Society: Spinach — hardiness
Checked 2026-08-13
- Hardiness ratingSourced guidancehigh confidence
- Royal Horticultural Society: RHS hardiness ratings
Checked 2026-08-13
- Grows best atHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Germinates atSourced guidancehigh confidence
Germinates in genuinely cold soil, which is what makes very early and very late sowings possible.
- OSU Extension Service — Oregon State University: Vegetable seed germination temperatures
Checked 2026-08-13
- SoilHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Soil pHSourced guidancehigh confidence
- University of Minnesota Extension — University of Minnesota: Soil pH for vegetable crops
Checked 2026-08-13
- DrainageHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Water needsHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- DroughtHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- WaterloggingHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- HeatSourced guidanceDepends on conditionshigh confidence
Applies when: Bolting is driven by DAY LENGTH as well as by temperature, so a cool but long June day still triggers it. This is why watering and shading do not save a midsummer sowing.
- Home and Garden Information Center — Clemson Cooperative Extension: Spinach — culture
Checked 2026-08-13
- Wind and exposureHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
On your soil
Computed by comparing this plant's recorded requirements against each soil's recorded characteristics. A recorded horticultural fact overrides the comparison where GrowingHQ holds one.
| Soil | Verdict | Why |
|---|---|---|
| Heavy clay | Works, with one condition | Spinach will crop on heavy clay, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. For a crop lifted before winter the risk is not rot but the season: waterlogged ground is cold and unworkable in spring, so sowing is late and germination patchy.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse. |
| Sandy | Works, with one condition | Spinach will crop on sandy, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure. |
| Chalky and alkaline | Works, with one condition | Spinach will crop on chalky and alkaline, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure. |
| Loam | Prefers this soil | Loam suits Spinach as it stands: The pH suits it: it wants 6.5 to 7.5, and this soil is in that range. Loam is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. There is ample rooting depth for it. |
| Silty | Prefers this soil | Silty suits Spinach as it stands: The pH suits it: it wants 6.5 to 7.5, and this soil is in that range. Silt is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. There is ample rooting depth for it. |
| Peaty and acid | Works, with one condition | Spinach will crop on peaty and acid, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. For a crop lifted before winter the risk is not rot but the season: waterlogged ground is cold and unworkable in spring, so sowing is late and germination patchy.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse. |
| Shallow over rock | Works, with one condition | Spinach will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure. |
| Made ground and urban soil | Works, with one condition | Spinach will crop on made ground and urban soil, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. For a crop lifted before winter the risk is not rot but the season: waterlogged ground is cold and unworkable in spring, so sowing is late and germination patchy.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse. |
Not sure which you have? Four hand tests will settle it.
Space and spacing
- Mature height
- 20–30 cm
- Mature spread
- 20 cm
- Rooting depth
- 20–30 cm
- Spacing
- 15 cm apart
- Row spacing
- 30 cm
Where these figures come from
- Mature heightHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Mature spreadHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Rooting depthHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- SpacingSourced guidancehigh confidence
- Royal Horticultural Society: Spinach — spacing
Checked 2026-08-13
- Row spacingSourced guidancehigh confidence
- Royal Horticultural Society: Spinach — spacing
Checked 2026-08-13
In a container
- Minimum volume
- 10 litres or more
- Minimum depth
- 20 cm
Where the container figures come from
- Minimum volumeSourced guidancehigh confidence
- Royal Horticultural Society: Spinach in containers
Checked 2026-08-13
- Minimum depthHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
Grows well in a pot if kept moist and out of the hottest afternoon sun; a container spinach that dries once will bolt. Best as a cut-and-come-again crop.
Where and how you can grow it
Each way of growing is assessed separately, and “not assessed” is a real answer rather than a gap we have filled in with a guess.
| Method | Suitability | What it needs |
|---|---|---|
| Open ground | Well suitedsourceSourced guidancehigh confidence
Checked 2026-08-13 | |
| Traditional dug bed | Well suitedsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | |
| Raised bed | Well suitedsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | |
| Container | Well suitedsourceSourced guidancehigh confidence
Checked 2026-08-13 | 20 cm of depth; Consistent moisture |
| Hydroponics | Well suitedsourceSourced guidancemoderate confidence
Checked 2026-08-13 | |
| Vertical growing | Well suitedsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | |
| Polytunnel | Well suitedsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | Extends both the autumn and the spring crop substantially. |
| Cold frame | Well suitedsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | The traditional way to carry spinach through a British winter. |
| Aquaponics | Well suitedsourceSourced guidancemoderate confidence
Checked 2026-08-13 | |
| Windowsill | WorkablesourceHorticultural consensusmoderate confidence As baby leaves, cut young. No external citation — see the evidence type above. Checked 2026-08-13 | A bright sill; Cutting at baby-leaf size |
| Greenhouse | WorkablesourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 |
Growing it
- SowingSow 2 cm deep directly where it is to grow. Spinach has a taproot and resents transplanting, so module-raising gains less than it does with lettuce.2 cm
- WateringKeep consistently moist. Drought stress brings bolting forward on a crop that is already inclined to it.
- HarvestingPick outer leaves and leave the centre growing, or cut the whole plant 3 cm above the crown for a second flush. Either way, pick often — large old leaves are coarse and the plant crops better for being kept young.
- FeedingSpinach is a nitrogen-hungry leaf crop and bolts when starved as readily as when dry. Grow it on ground manured for a previous crop and give a liquid nitrogen feed to plants being cut repeatedly.
Where this guidance comes from
- SowingSourced guidancehigh confidence
- Royal Horticultural Society: Spinach — sowing
Checked 2026-08-13
- WateringHorticultural consensusmoderate confidence
- Royal Horticultural Society: Spinach — watering
Checked 2026-08-13
- HarvestingSourced guidancehigh confidence
- Royal Horticultural Society: Spinach — harvesting
Checked 2026-08-13
- FeedingSourced guidancemoderate confidence
- Royal Horticultural Society: Spinach — cultivation
Checked 2026-08-13
Is it worth putting under cover?
Whether it will grow there is on the methods table above. This is whether the space is well spent, which is a different question and usually the one being asked.
| Structure | What protection is worth | What decides it |
|---|---|---|
| Greenhouse | Extends the seasonsourceGrowingHQ editorial positionmoderate confidence What protection is worth for this crop, judged against the same standard as every other record in this file.
Checked 2026-08-13 | Bolting and winter light. Spinach bolts in summer heat under glass and is one of the best winter crops there — the seasons are the reverse of what people expect. |
| Polytunnel | Extends the seasonsourceGrowingHQ editorial positionmoderate confidence What protection is worth for this crop, judged against the same standard as every other record in this file.
Checked 2026-08-13 | Bolting and winter light, on the same inverted seasonality. |
Growing it without soil
Nearly anything can be grown in a soilless system by somebody with enough equipment. The useful question is whether it is worth it, in which technique, and what goes wrong.
An established soilless crop. Grown this way commercially or routinely by home growers, with predictable results.
source
Sourced guidancemoderate confidence
- Purdue Extension — Purdue University: Hydroponic leafy greens
Checked 2026-08-13
Suits soilless growing for the same reasons lettuce does, with the bonus that day length can be controlled — the one thing that defeats it outdoors.
Techniques that suit it
- Nutrient film (NFT)A shallow stream of solution runs over bare roots in a sloped channel. Cheap and productive for small fast crops; a pump failure kills a crop within hours because there is no reservoir at the roots.
- Deep water cultureRoots hang in aerated solution. Very productive and very unforgiving of solution temperature — warm solution holds less oxygen and root disease follows.
- Ebb and flowA bed of inert medium floods and drains on a timer. The medium holds moisture between floods, which makes it far more tolerant of interruption than NFT.
source
Horticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Root space
- Shallow, like lettuce, though the taproot suits a medium bed slightly better than bare channels.
- Lighting
- Needs supplementary light
- pH band
- 5.5–6.5
Where these figures come from
- Root spaceHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- LightingHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- pH bandSourced guidancehigh confidence
Outside roughly this band, individual nutrients become unavailable even when they are present in the solution — which is why a crop can starve in a full reservoir.
- Purdue Extension — Purdue University: Hydroponic solution management — pH
Checked 2026-08-13
What actually goes wrong
- Bolting under long lit days — the same trigger that ends it outdoors in midsummer. Controlling the photoperiod is the advantage a closed system has here.
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Spinach bolting
Checked 2026-08-13
- Warm solution. Above roughly 22 °C the water holds much less dissolved oxygen and root disease follows quickly, which is why summer is harder than winter in an indoor system.
source
Sourced guidancemoderate confidence
- Purdue Extension — Purdue University: Solution temperature and dissolved oxygen
Checked 2026-08-13
No nutrient recipes here
GrowingHQ records pH bands, which are measurable properties of nutrient availability, and deliberately records no EC or PPM targets and no mixing instructions. Published targets vary by cultivar, growth stage, water source and technique, and the figures that apply to your system are on the product you bought.
Harvesting
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Spinach — timing
Checked 2026-08-13
- When it is readyUsable from baby-leaf size. Pick before any sign of a central stem elongating, which is the start of bolting.
- How to pick itCut individual leaves, or the whole plant above the crown.
- Keeping itA few days refrigerated. Wilts fast; better picked immediately before use.
Where the harvest guidance comes from
- When it is readyHorticultural consensusmoderate confidence
- Royal Horticultural Society: Spinach — harvesting
Checked 2026-08-13
- How to pick itHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Keeping itHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
Keep picking
What goes wrong
| Problem | How often | Notes |
|---|---|---|
| Bolting | commonsourceSourced guidancehigh confidence
Checked 2026-08-13 | The defining problem of the crop, and driven by day length as much as by heat. |
| Slugs and snails | commonsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | |
| Aphids | occasionalsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 |
Start from what you can see
Grown with, grown after, grown instead
Every relationship states its mechanism. A pairing nobody can explain is a pairing nobody has checked, and it does not go in.
- Alternative toKaleKale supplies leaves through the winter months when spinach has died back, and through the midsummer weeks when spinach bolts — the two together give leafy greens most of the year.
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Winter leafy vegetables
Checked 2026-08-13
- Closely relatedBeetrootBoth are Amaranthaceae, and the leaf beet sold as 'perpetual spinach' is the same species as beetroot rather than true spinach. This is why beetroot tops taste of spinach and why the two share a rotation slot.
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Leaf beet and spinach
Checked 2026-08-13
Safety and edibility
- Preparationsensitised individualsSpinach is high in oxalates, as chard and beet leaves are. This matters for anyone advised to limit oxalate intake, for example because of a history of kidney stones.
source
Horticultural consensusmoderate confidence
- Home and Garden Information Center — Clemson Cooperative Extension: Spinach — nutrition
Checked 2026-08-13
Not a concern for general use. Anyone advised to limit oxalates should treat spinach as one of the higher-oxalate vegetables.
Sources for this page
GrowingHQ editorial synthesis · Home and Garden Information Center · OSU Extension Service · Purdue Extension · Royal Horticultural Society · University of Minnesota Extension
Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-13.
If something is wrong with it
- Plant running up to flower before it is ready to eat — 2 causes GrowingHQ holds for spinach
Something else? Work through it with the diagnostic tool.