Straw foxglove

Questions about straw foxglove

Does straw foxglove need sun or shade?

Straw foxglove grows in part sun (4 to 6 hours of sun, including some afternoon sun) and part shade (2 to 4 hours of sun, mostly in the morning).

It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells.

What zones does straw foxglove grow in?

USDA zones 3 to 8. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).

Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.

Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.

When does straw foxglove flower in my zone?

In zone 5 it flowers mid June to late July. As a summer flower it moves about half a week for every zone: earlier where it is warmer.

Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.

How far apart should straw foxglove be planted?

12 in (30 cm) apart, from the middle of one plant to the middle of the next. That is about its full width, so each plant keeps its own outline.

It grows 2½ ft (75 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.

How many straw foxglove plants do I need?

At 12 in apart, set out in staggered rows:

• 12 to fill 10 square feet (about 1 m²)
• 11 for a single row 10 ft (3 m) long
• 38 to fill a 4 × 8 ft bed on its own

In a mixed border, plant it as one at a time, repeated along the bed at intervals; a slender one reads better as a clump of three.

In the bed above, the planner used five in five groups.

Is straw foxglove poisonous to dogs and cats?

Yes: severe toxicity to people, dogs, cats and horses. All parts are highly poisonous if eaten and affect the heart; even small amounts can be life-threatening. Avoid it where children or pets may chew plants.

Rated from the ASPCA. Where references disagree, the more cautious rating is used.

Is there a pet-safe plant like straw foxglove?

These come closest to doing what straw foxglove does, and no toxicity is recorded for them:

• Peach-leaved bellflower: the same job in a bed, the same size and the same flowering time; blue or white, not yellow, fine leaves, not medium.
• Balloon flower: a drift, not an accent, 6 in shorter.
• Purple moor grass 'Moorhexe': the same job in a bed and the same size; flowers mid July to early September, purple, not yellow.

Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.

Will straw foxglove spread?

It seeds itself about; the risk of it taking over is moderate. Self-seeds around the parent plant. Pull unwanted seedlings.

What flowers after straw foxglove?

Straw foxglove is over by late July. These start as it finishes and carry the same spot on, so it never goes flat:

• Lilyturf: from early August to mid September, 16 in tall, to stand in front of it and cover its fading stems.
• Japanese anemone: from mid August to early October, 3 ft tall.
• Garden phlox: from mid July to early September, 3½ ft tall.

What does straw foxglove look like in winter?

Straw foxglove holds some of its leaves into winter, more in a mild year or a sheltered spot, and they look tired by March. Cut the old ones off as new growth starts.