Mature size & growth rate

How big does Foxglove (Digitalis purpurea) get?

Also called Foxglove, Common Foxglove, Lady's Glove, Fairy Fingers.

More about foxglove

About Foxglove

Digitalis purpurea · also called Foxglove, Common Foxglove · flowering

Digitalis purpurea is a tall biennial or short-lived perennial native to western and central Europe, including the UK, where it is a quintessential woodland-edge and cottage-garden plant. In its first year it forms a large flat rosette of velvety leaves; in its second it throws up a commanding spike of tubular, spotted flowers beloved by bumblebees. The most important care fact is to site it in partial shade with moisture-retentive, humus-rich soil, and to allow self-seeding for a continuous display. Every part of this plant is highly toxic to pets and humans.

Mature size: 100–180 cm tall in flower (3–6 ft), with a first-year rosette spread of 40–60 cm.

Watch for — Aphid infestation on flower spike: Foxglove aphids (Acyrthosiphon cyparissiae) and other species colonise the developing flower spikes in late spring, causing stunted or distorted flowers; knock off with a strong water jet or introduce ladybird larvae.

Indoor size vs how big it gets in the wild

Foxglove reaches its full size within one growing season — there is no "long-term" size, just how big it gets before you harvest or it dies back. Indoors and in a pot, expect 100–180 cm tall in flower (3–6 ft), with a first-year rosette spread of 40–60 cm.. A pot, your light levels and a little pruning are what set the final size in a home, far more than the plant's theoretical potential.

It sizes up fast and once, racing from seedling to full size in a single season; after cropping it is finished, so size is a within-season question.

Growth rate and years to mature

Foxglove is a moderate grower. Realistically, expect a single growing season — it reaches full size in one year, then is done. Its feeding profile backs this up: mulch with leafmould or garden compost in autumn; a single application of a balanced slow-release fertiliser in spring of the second year supports stem development without producing soft tissue susceptible to powdery mildew.

Want this turned into the right next pot at the right moment? The pot size calculator and the foxglove repotting guide cover when and how much to size up — pot size is one of the biggest levers on how fast foxglove grows.

How to keep foxglove smaller

You are not stuck with the maximum size. For foxglove specifically, these are the levers, in order of impact:

Choose a compact or dwarf variety of foxglove from the start — that is the most reliable size control for an annual.
Grow it in a smaller container to naturally limit how large it gets.
For some crops, pinching or pruning the growing tips keeps the plant shorter and bushier.
Sow a little later or space plants closer if you specifically want smaller individual plants.

How to grow foxglove bigger or faster

If you want it to fill the space sooner, push the conditions rather than hoping — for foxglove the accelerators are:

Full sun, warm soil and steady water are what drive a crop to full size fastest.
Sow at the right time for your zone so it gets the whole season to size up.
Feed appropriately for the crop and never let it check (stall) from drought or cold.

Light is almost always the ceiling. The foxglove light requirements page covers exactly how bright a spot it needs to grow at its potential instead of stalling.

When foxglove outgrows the room (or the pot)

"Too big" usually arrives as one of these signs for foxglove:

It sprawls beyond its bed or container before harvest — usually a spacing or support issue.
It flops or needs staking once it hits full height.
Once it has fruited or bolted, it is at its final size for good — the next plant is a new sowing.

If it is the pot rather than the room, it is a repotting job, not a goodbye — see the foxglove repotting guide. If you want more of this plant instead of a bigger one, the foxglove propagation guide turns prunings into new plants.

Foxglove size — frequently asked questions

How big does foxglove get?

Foxglove reaches 100–180 cm tall in flower (3–6 ft), with a first-year rosette spread of 40–60 cm. when grown indoors. It sizes up fast and once, racing from seedling to full size in a single season; after cropping it is finished, so size is a within-season question.

Is foxglove slow or fast growing?

Foxglove is a moderate grower. Expect a single growing season — it reaches full size in one year, then is done. Foxglove reaches its full size within one growing season — there is no "long-term" size, just how big it gets before you harvest or it dies back.

How long does foxglove take to reach full size?

Roughly a single growing season — it reaches full size in one year, then is done. Light, pot size and feeding move that timeline more than anything else.

How do I keep foxglove smaller?

Choose a compact or dwarf variety of foxglove from the start — that is the most reliable size control for an annual. Grow it in a smaller container to naturally limit how large it gets. For some crops, pinching or pruning the growing tips keeps the plant shorter and bushier. Sow a little later or space plants closer if you specifically want smaller individual plants.

How can I make foxglove grow bigger or faster?

Full sun, warm soil and steady water are what drive a crop to full size fastest. Sow at the right time for your zone so it gets the whole season to size up. Feed appropriately for the crop and never let it check (stall) from drought or cold.