Plants for chalky soil with white & blue flowers
Plenty of plants, of a variety of shapes, sizes and colours, thrive in the higher pH of chalky soil, so it’s perfectly possible to create a full and attractive border even in these sometimes challenging conditions
Quick facts
- Chalky or limey soils can benefit from the addition of plenty of organic matter to improve water retention
- Chalky soils drain quickly, even in wet weather, so can be good for Mediterranean plants
- Some plants do their best colours in chalky soil
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The planting plan
This white and blue planting design provides a range of plants that, once established, will thrive in chalky or limey soil to provide a variety of interest throughout the year. A simple planting plan helps to create depth, interest and good coverage in a border.
White and blue plants for chalky soil
Choosing plants for chalky soil
These plants have been selected because their preferred growing condition is alkaline soil. By using plants that are naturally adapted to these conditions, we can enjoy healthier plants and lower inputs compared with trying to grow plants that are less well suited.
The Geranium provides some groundcover and will help prevent erosion of bare soil. The groundcover can also help to reduce evaporative moisture loss from the soil surface and suppress weed growth.
Additional organic mulching, preferably with homemade compost, can further improve soil moisture retention and weed suppression. Mulches should be spread when the soil is already moist, to help trap some of that moisture before it dries out in summer.
Viburnum x burkwoodii ‘Mohawk’
Persicaria microcephala ‘Red Dragon’
Choisya x dewitteana ‘Aztec Pearl’
Geranium ‘Orion’
Thalictrum ‘Black Stockings’
Ceanothus ‘Skylark’
Agapanthus ‘Midnight Star’
2 - Persicaria microcephala ‘Red Dragon’ is a herbaceous perennial that provides dark purple foliage with a striking silver splash, and white flowers in late summer.
3 - Choisya x dewitteana ‘Aztec Pearl’ is a small evergreen shrub with bright green leaves, each comprising 3-5 slender leaflets. The pink-tinged buds open to clusters of fragrant white flowers in late spring and often repeat in autumn.
4 - Geranium ‘Orion’ is a herbaceous perennial forming a spreading mound of deeply lobed green leaves. Sky-blue flowers with thin purple veins and a white eye are produced through the summer.
5 - Thalictrum ‘Black Stockings’ is a tall herbaceous perennial with lacy foliage and upright, near-black stems bearing sprays of fluffy clear purple-pink flowers in summer.
6 - Ceanothus ‘Skylark’ is an evergreen shrub with small glossy leaves, which becomes smothered in clusters of deep blue flowers in late spring to early summer.
7 - Agapanthus ‘Midnight Star’ is a striking hardy perennial with dark strap-like leaves and round heads of trumpet-shaped cobalt blue flowers with darker blue stripes in early summer.
About alkaline, chalky soils
Once the plants are established, this will also reduce the need for extra inputs that less well-adapted plants would need, such as fertilisers and frequent watering.
The challenge of growing on chalky soils
Why choose a sustainable planting combination
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