How to Grow Sea Holly (Eryngium) Flowers

Eryngium prefers full sun - at least 6 hours of direct sunlight per day. Eryngium prefers dry, poor to moderately fertile, well-drained soils with the exception of Eryngium pandanifolium (Giant Sea Holly) which prefers moist soils. Good drainage is critical or your plant will die off from root rot.

How do you grow Eryngium blue sea holly?
How do you grow Eryngium?
How long does Eryngium take to grow?
Does sea holly dieback in winter?
Is blue sea holly invasive?
Can you take cuttings from sea holly?
Is Eryngium a perennial?
Is Eryngium poisonous to cats?
How do you care for Eryngium Big Blue?
Should I cut back sea holly?
Is Eryngium deer resistant?
Can I grow sea holly in a container?

How do you grow Eryngium blue sea holly?

All types will thrive in full sun and moist soil with good drainage. In fact, they actually prefer sandy soil. The long taproot, however, allows the plant to tolerate poor soil conditions and drought. Because of their taproot, locate sea hollies somewhere permanent, as they do not transplant easy.

How do you grow Eryngium?

Eryngiums need plenty of sunshine and free-draining soil. They can tolerate poor soil, and a spot at the foot of a wall is a good position as the soil will remain dry over winter. It's also a good idea to plant eryngiums away from the edge of a border or path, as their spikes can be quite sharp.

How long does Eryngium take to grow?

Germination is erratic, between 5 and 90 days. As each seed germinates we would recommend that you transplant into its own compostable growing cell using gritty compost to grow on until large and strong enough to be planted out into a sunny position.

Does sea holly dieback in winter?

When it blooms

Summer-flowering sea hollies provide a long-lasting flowerhead that eventually browns and fades, giving months of value. These sea hollies die down completely in winter and, given good drainage, will return every year.

Is blue sea holly invasive?

Eryngium Sea Holly self-sows readily by dropping its flower seeds on the ground, but it is not invasive. If the Sea Holly seeds are started indoors, transplant the seedlings where you want them to grow when they are quite small. The Eryngium plants have taproots, so they won't transplant well once mature.

Can you take cuttings from sea holly?

Eryngium, or sea holly, is a plant that can be propagated by root cuttings.

Is Eryngium a perennial?

Eryngium or “Sea Holly” is a lovely addition to the shrub border with silver or silver-blue thistle-like leaves and flowers with a distinctive spiney ruff around them. They flower for about three months and you can leave the spent flower heads on the plant for winter interest.

Is Eryngium poisonous to cats?

Is Eryngium varifolium poisonous? Eryngium varifolium has no toxic effects reported.

How do you care for Eryngium Big Blue?

For best results grow Eryngium x zabelii 'Big Blue' in free-draining soil, in a sunny position. In colder climates you may need to protect the roots with a mulch of straw, and tidy spent foliage in spring to prevent rot.

Should I cut back sea holly?

Selective cutting back in autumn can retain the dried, bleached flowerheads of plants, while removing material showing signs of decay or fungal growth. Examples include: such as Eryngium (sea holly), Phormium (New Zealand flax) and the foliage and flowers of ornamental grasses.

Is Eryngium deer resistant?

Eryngium planum 'Blaukappe'

Deer, rabbit, and drought tolerant, and extremely salt tolerant. Creates structure for the fall and winter garden, and perfect along a winter salted parking lot, or dry meadow.

Can I grow sea holly in a container?

Beyond the garden, mixing 'Big Blue' Sea Holly with other perennials creates beautiful and novel containers. Plants are also useful for cut and dried flowers, are attractive to butterflies and have a long bloom period in summer.