The river star

A South-African shrub - cousin of the Buddleia.
Common name : The river star
Scientific name : Gomphostigma virgatum
Family : Scrophulariaceae
Category : Shrubs
Type of plant : Perennial
Wind resistant
Wind resistant
Cold-sensitive
Cold-sensitive
Flowery
Flowery
Gomphostigma is an evergreen arching shrub growing up to to 1.5m with narrow, stemless silvery leaves and tiny white star-shaped flowers in small clusters. Plant in full sun to light shade. It’s hardy to -10°C, and low maintenance.

Sowing & planting

J
F
M
A
M
J
J
A
S
O
N
D

Flowering

J
F
M
A
M
J
J
A
S
O
N
D

Caracteristics

Exposition
Water needs
Granulométrie plants.granulometry_1
Frost-resistance Medium
Zone USDA 9a
Height 100 - 150
pH 6.3 - 6.7

Plant my river star

Plant your gomphostigma in a sunny position, in a very well drained soil or sandy, neutral acid. It will enjoy a bit of shade during the hottest hours of the day. Plant in open soil, in the spring so that it is sufficiently rooted to support the first winter. The gomphostigma will only support short frosts: in areas where frost is common, grow it in pot in order to shelter it in winter.

Protect my river star

To help it through winter, protect your plant from cold winds — these are its only real enemy! — by spreading a good layer of mulch at its base. In this manner, even in the case of heavy frosts, new branches will sprout from the plant. If your plant is potted, shelter it from winds by moving it closer to a wall, by potentially raising it from direct contact with the ground, and if possible, protecting the pot itself by wrapping it with burlap, and possibly stuffed with straw.

Water my river star

Your Gomphostigma grows in its natural habitat on river banks, its roots in water, but remains relatively resistant to drier conditions. Water sparingly for a few weeks after planting, and in the summer in case of drought : check the needs by pushing your finger a few inches deep in the substrate, and water if it is dry underneath. If grown in a pot, and depending on the size of the pot, you may need to water fro time to time - same thing, check with your finger and water only if needed!

Repot my river star

If you keep your gomphostigma potted, if possible repot every 2 to 3 years, in a simple potting soil and a slightly larger pot. Otherwise, scrape and remove the upper layer of the mixture, and replace it with some new potting soil or some well decomposed compost.

Prune my river star

A vigorous trim in late winter or early spring to help maintain it's bushy shape and increase its future flowering is all this plant needs!

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