Preslia cervina alba
Blue water spearmint, Hart's pennyroyal, Holt's pennyroyal
Also known as Mentha cervina alba, Preslia cervina 'Alba'
- Height × spread
- 0.4m × 1m
- Position
- Full sun
- Hardiness
- Colder than -20C (RHS H7)
- Flowers
- Summer
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
A useful marginal plant that can be grown in moist or boggy soil or water to a depth of 10cm. It is upright with slender horizontally held leaves and white flowers in midsummer. It can be used as a substitute for pennyroyal (Mentha pulegium). It has a minty, aromatic fragrance.
- Flower colour
- White
- Foliage colour
- Green
- Variegated
- No
- Scent
- No
- Shape
- Dome
- Height
- 0.4m
- Spread
- 1m
- Season of interest
- Spring, Summer, Autumn
- Flowers in
- Summer
- Evergreen
- Evergreen
- Garden style
- Water garden
- Sun or shade
- Likes full sun, tolerates part shade, tolerates light shade
- Soil type
- Chalk, Loam (normal)
- Soil pH
- All types
- Drainage
- Moisture retentive soil
- Hardiness
- Colder than -20C (RHS H7)
- Borders & containers
- Borders
- Water depth
- Up to 25cm
- Use for
- Deer resistant, Rabbit resistant, Butterfly attraction
- Hazards
- No
Spring
Spring · Outdoors
Feed with aquatic plant food
As the plant is grown in water, feed with an aquatic feed as directed on the packet. Do not exceed the amounts given as this can affect the water.
Spring-Autumn · Outdoors
Water frequently to keep the soil moist
The plant thrives in moist or boggy soil, doesn't tolerate dryness and should be watered frequently, not only after a period of drought, but if the soil begins to dry out spring to autumn. Check plants in pots more frequently, especially in hot weather.
Spring · Planting
Divide when too large
The plant can be divided in alternate years. Clumps may be divided into two or more pieces. Rhizomes can be cut whilst small bulbs or offsets are detached. The new plants can be grown in a container or planted in the ground.
Summer
Summer · Planting
Prune after flowering
When the plant has finished flowering, cut the trailing stems back by half their length or more to retain a compact and appealing habit.
Planting & general
Compost · Planting
Compost for aquatic plants
Use aquatic plant compost for pond plants (other composts contain nitrates that cause problems in ponds). Pond plants are generally planted in baskets and weighted to keep in position.