Alkaline soils are those that have a high pH, usually as a result of being rich in chalk or limestone.

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In the UK, these soils are often found on chalk downlands, including areas like the South Downs, Chiltern Hills and Salisbury Plain. If you live in an area with limestone deposits, your soil is also likely to be alkaline.

To be certain of your soil pH, test your soil pH with a kit from the garden centre, or online.

Ericaceous, lime-hating plants shouldn't be planted in alkaline soils, as they can't take up important nutrients like iron.

Discover the best plants for alkaline soils that you can grow, below.

Lily of the valley

If you're looking for a ground cover plant for alkaline soils, consider lily of the valley. The flowers are sweetly scented and there are several attractive cultivars to grow, including 'Albostriata' and 'Hardwick Hall'.

Lily of the valley, Convallaria majalis
White bells of lily of the valley

Phacelia

Though often grown for green manure, it's worth letting phacelia flower to witness its ability to attract numerous pollinators. It's part of the borage family Boraginaceae, which includes lots of other lime-loving plants like borage, viper's bugloss and anchusa.

Phacelia flower
Mauve phacelia flowers

Ornamental clovers

Ornamental clovers like Trifolium rubens and Trifolium ochroleucon are star-performers on chalky soils. In fact, most plants in the legume family (Fabaceae) dislike acid soils.

Trifolium ochroleucon
White ornamental clover flowers

Wild marjoram

Wild marjoram, or oregano (Origanum vulgare) is easy to grow if given plenty of sun and well-drained soil. Cultivars to grow include 'Aureum' and 'Compactum'. A popular plant for butterflies.

Wild marjoram Origanum vulgare
Wild marjoram flowering pale pink

Polemoniums

Jacob's ladder plant (Polemonium caeruleum) is a pretty, native perennial that will relish a moist, lime-rich soil. If the soil is quite thin, improve before planting by incorporating lots of organic matter such as leaf mould and well-rotted manure.

Polemonium in flower
Blue polemonium flowers

Sesleria caerulea

This native, evergreen grass is commonly known as blue moor grass, owing to the glaucous uppersides of the foliage. Grow Sesleria caerulea in full sun and expect it to gradually spread.

Sesleria caerulea
Evergreen blue moor grass

Lavender

Lavender, as well as other aromatic plants like rosemary, thyme and artemisia, will enjoy the free-draining soil provided by chalky soils. Grow them in full sun to get the best from them.

Lavandula angustifolia 'Purple Treasure'
Lavender 'Purple Treasure'

Honeysuckle

Our native honeysuckle, Lonicera periclymenum, does well in a variety of settings, and there are plenty of cultivars to grow, including 'Graham Thomas' and 'Serotina'. Overgrown honeysuckle? Find out out to prune honeysuckle.

Lonicera 'Serotina'
A honeysuckle bloom

Spindle

Spindle, Euonymus europaeus, is a native shrub or small tree. The autumn colour is spectacular and, when the leaves have fallen, brightly-coloured fruits remain to provide interest.

Euonymus europaeus
Vivid pink-winged, orange fruit of the spindle tree

Lilac

Lilacs (syringa) grow best on chalky soils. Planted here, you'll be rewarded with richly scented flowers and attractive, heart-shaped leaves.

Lilac 'Red Pixie'
Pale-pink flowers of lilac 'Red Pixie'
Using a soil testing kit
Measuring soil pH

Getting the best from alkaline soils

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