Foxglove
Digitalis purpurea
Before you grow or eat this
Every part is highly poisonous. It contains cardiac glycosides that act directly on the heart, and serious poisoning has followed eating small quantities. The first-year leaf rosette is the particular danger: it resembles comfrey and borage closely enough that foragers have picked it in mistake for them and been poisoned making tea. Never eat any part of it, and never harvest leaves for tea from a rosette you have not positively identified. Wear gloves when handling, wash hands afterwards, and seek immediate medical advice if any part is swallowed.
A native biennial for shade: a rosette of leaves in the first year, a tall flower spike in the second, and then it dies having seeded itself around. It is also one of the most poisonous plants commonly grown in gardens, and its first-year rosette is mistaken for comfrey often enough to matter.
- Position
- Partial shade or Dappled shade
- Water
- moderate demand
- Drainage
- Moisture-retentive, Free-draining
- Grows to
- 90–180 cm × 30–45 cm
- Hardiness
- H6
- Flowers
- June and July
- Difficulty
- Straightforward
Described view
A first-year foxglove leaf rosette beside a comfrey rosette, showing the differences in leaf texture and vein pattern
August
Nothing to do
No sowing, planting, harvesting or pruning window falls in August.
Coming next month: plant.
Foxglove’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 | May. | June. | July. | |||||||||
| Plant | March. | September. | October. | |||||||||
| In flower | June. | July. |
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.
Conditions it needs
- Light
- Partial shade, Dappled shade
- Frost
- Very hardy
- Hardiness rating
- H6 (RHS)
- Grows best at
- 10–24 °C
- Soil
- Loam, Clay, Sandy
- Soil pH
- 5–7
- Drainage
- Moisture-retentive, Free-draining
- Water needs
- moderate
- Drought
- moderate tolerance
- Waterlogging
- poor tolerance
- Heat
- moderate tolerance
- Wind and exposure
- moderate tolerance
Where these figures come from
- LightSourced guidancemoderate confidence
- Royal Horticultural Society: Foxglove — position
Checked 2026-08-13
- FrostSourced guidancehigh confidence
- Royal Horticultural Society: Foxglove — hardiness
Checked 2026-08-13
- Hardiness ratingSourced guidancemoderate confidence
- Royal Horticultural Society: RHS hardiness ratings
Checked 2026-08-13
- Grows best atSourced guidancemoderate confidence
- Royal Horticultural Society: Foxglove — temperature
Checked 2026-08-13
- SoilSourced guidancemoderate confidence
- Royal Horticultural Society: Foxglove — soil
Checked 2026-08-13
- Soil pHSourced guidancemoderate confidence
- Plant Finder — Missouri Botanical Garden: Digitalis purpurea — culture
Checked 2026-08-13
- DrainageSourced guidancemoderate confidence
- Royal Horticultural Society: Foxglove — soil
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
- HeatHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Wind and exposureHorticultural consensusmoderate confidence
Tall spikes need shelter or they lean.
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 | Foxglove will crop on heavy clay, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.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 | Prefers this soil | Sandy suits Foxglove as it stands: The pH suits it: it wants 5 to 7, and this soil is in that range. The free drainage is exactly what it wants. Sandy soil is among the soils it is recorded as suiting. |
| Chalky and alkaline | Works, with one condition | Foxglove will crop on chalky and alkaline, but one thing has to be dealt with first. The soil is substantially too alkaline for it: it wants pH 5 to 7, and this soil sits around 7.8 to 8.5.The pH is the obstacle. Small shifts are achievable and slow; large ones are not. On chalky and alkaline the dependable answer is a container of the right compost rather than an attempt to change the ground. |
| Loam | Prefers this soil | Loam suits Foxglove as it stands: The pH suits it: it wants 5 to 7, and this soil is in that range. The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. |
| Silty | Prefers this soil | Silty suits Foxglove as it stands: The pH suits it: it wants 5 to 7, and this soil is in that range. The free drainage is exactly what it wants. The soil holds moisture, which saves a great deal of watering. |
| Peaty and acid | Works, with one condition | Foxglove 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. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.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 | Prefers this soil | Shallow over rock suits Foxglove as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. |
| Made ground and urban soil | Works, with one condition | Foxglove 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. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.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
- 90–180 cm
- Mature spread
- 30–45 cm
- Rooting depth
- 30 cm
- Spacing
- 30–45 cm apart
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 guidancemoderate confidence
- Royal Horticultural Society: Foxglove — spacing
Checked 2026-08-13
In a container
- Minimum volume
- 5 litres or more
- Minimum depth
- 30 cm
Where the container figures come from
- Minimum volumeHorticultural consensusmoderate confidence
- Royal Horticultural Society: Digitalis purpurea — cultivation
Checked 2026-08-13
- Minimum depthHorticultural consensusmoderate confidence
- Royal Horticultural Society: Digitalis purpurea — cultivation
Checked 2026-08-13
Works, with the caveat that a foxglove is biennial and a pot therefore holds a rosette of leaves doing nothing for a whole year before it flowers. Most people who grow them in containers raise the young plants in pots and move them into a border in autumn, which is the sensible arrangement. Deep enough for the taproot, and remember that every part of the plant is poisonous when placing it.
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 guidancemoderate confidence
Checked 2026-08-13 | |
| Raised bed | Well suitedsourceSourced guidancemoderate confidence
Checked 2026-08-13 | |
| Container | MarginalsourceSourced guidancemoderate confidence
Checked 2026-08-13 |
Growing it
- SowingScatter the seed on the surface and do not cover it. Foxglove seed needs light to germinate, and burying it is the usual reason a sowing fails entirely.
- PruningLeave one or two spikes to seed if you want it to continue, and cut the rest down. As a biennial the parent plant dies after flowering whatever you do, so a colony is maintained by seedlings rather than by the original plants.
- WateringWater young plants through their first summer, and again in a dry spring in their flowering year — a foxglove is biennial, so the plant that is a flat rosette of leaves this autumn is the one that will send up a spike next June, and a dry spell while that spike is extending gives a short one. Established plants in the light shade they prefer generally need nothing. They are woodland-edge plants and dislike both baking sun and waterlogged ground.
- FeedingNot needed and best avoided. Foxgloves grow perfectly well on poor woodland-edge soil, and a fed plant makes a tall soft spike that leans or breaks. What actually keeps foxgloves going in a garden is letting some of them seed: they are biennials, so a colony persists by producing a new generation of rosettes each year, and deadheading everything tidily is the reliable way to have none at all in two years' time. Every part of the plant is poisonous, so handle it with that in mind.
Where this guidance comes from
- SowingSourced guidancehigh confidence
- Royal Horticultural Society: Digitalis — propagation
Checked 2026-08-13
- PruningSourced guidancehigh confidence
- Royal Horticultural Society: Digitalis — cultivation
Checked 2026-08-13
- WateringSourced guidancemoderate confidence
- Royal Horticultural Society: Digitalis purpurea — cultivation
Checked 2026-08-13
- FeedingSourced guidancemoderate confidence
- Royal Horticultural Society: Digitalis purpurea — cultivation
Checked 2026-08-13
What goes wrong
| Problem | How often | Notes |
|---|---|---|
| Normal biennial cycle | commonsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | A flat rosette and no flowers in year one is the plant on schedule. |
| Slugs and snails | commonsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 |
Safety and edibility
Listed as harmful to cats or dogs
Foxglove is listed as harmful if eaten. Every part contains cardiac glycosides, which act directly on heart muscle in the same way the derived drug does. Poisoning produces vomiting, an abnormal heart rate and collapse, and the dose that matters is small. This is one of the few garden plants where a suspected mouthful is an emergency rather than a wait-and-see.source
Sourced guidancehigh confidence
- ASPCA Animal Poison Control Center — toxic and non-toxic plant list — American Society for the Prevention of Cruelty to Animals: Digitalis purpurea — toxic plants list
- Veterinary Poisons Information Service — VPIS, London: Digitalis purpurea — clinical effects
Checked 2026-08-13
Affected parts: all parts.
- ToxicitychildrenpetsEvery part is highly poisonous. It contains cardiac glycosides that act directly on the heart, and serious poisoning has followed eating small quantities. The first-year leaf rosette is the particular danger: it resembles comfrey and borage closely enough that foragers have picked it in mistake for them and been poisoned making tea.
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Digitalis purpurea — toxicity
- Plant Finder — Missouri Botanical Garden: Digitalis purpurea — toxicity
Checked 2026-08-13
Never eat any part of it, and never harvest leaves for tea from a rosette you have not positively identified. Wear gloves when handling, wash hands afterwards, and seek immediate medical advice if any part is swallowed.
Sources for this page
GrowingHQ editorial synthesis · Plant Finder · Royal Horticultural Society
Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-14.