Choosing Plants for Chalk Soil
Perennials and Climbers

Choosing plants for chalk soil can seem a bit of a problem so I've picked out a few of my own favourite perennials and climbers.

If you garden on chalky soil you will need plants that can cope with quite a high (strongly alkaline) pH, and also with the shallow topsoil that is typical of chalk areas.

Some of the selected plants for chalk soil really thrive in these conditions, others are chalk tolerant but should still do well.

If you think your soil is very alkaline but are not certain, do take a small amount of time and trouble to carry out a simple soil pH test using either a soil pH test kit or soil pH meter.

If you would like some ideas for trees and shrubs for chalk soil go to Choosing Plants for Chalk Soil: Trees and Shrubs.

Don't forget, if you would like to extend the range of plants you can grow, you can improve or amend very thin chalk soils by adding plenty of organic matter.

Perennials for Chalk Soil

Bergenia 'Ballawley' (Elephant Ears)

Plants for Chalk Soil, Bergenia Ballawley, Elephant Ears
Form:
perennial
Foliage:
evergreen
Hardiness:
UK - hardy; USDA zones 3 to 8
Soil:
any well drained soil; tolerates chalk
Situation:
sun or partial shade
Height:
60cm (24in)
Spread:
60cm (24in)
Awards:
RHS AGM

Reasons to grow: Splendid large leathery leaves turning bronze red in winter. Spikes bearing clusters of crimson flowers in early spring. Excellent evergreen ground cover also useful for softening the edges of paths and borders.

Also consider: Bergenia cordifolia for pink flowers; B. cordifolia 'Purpurea' for bronze winter foliage and magenta flowers; the smaller Bergenia 'Silberlicht' (30x50cm, 12x20in) has white flowers flushed pink.

Centranthus ruber (Red Valerian)

Perennials for chalky soil, Centranthus ruber, Red Valerian
Form:
perennial
Foliage:
deciduous
Hardiness:
UK - hardy; USDA zones 5 to 8
Soil:
thrives on chalk but will grow in any poor well-drained soil
Situation:
sun
Height:
90cm (3ft)
Spread:
60cm (2ft)

Reasons to grow: This cheery cottage garden plant is easy to grow and has a charmingly informal air. It is also highly attractive to beneficial insects.

The upright stems carry lance shaped, fleshy, glaucous leaves and it is smothered in frothy heads of reddish pink flowers from late spring through to autumn.

It positively thrives in poor conditions and will pop up in the most unexpected places such as in the cracks and crevices in walls and paving.

As you may have gathered by now, it is an enthusiastic self-seeder. To prevent this, and prolong the flowering season, deadhead regularly.

If different coloured variants are growing nearby it will not breed true but you may be pleasantly surprised by the results which can vary from white through soft pink to red.

Also consider: 'Albus', the pure white form, and 'Atrococcineus' which is a deeper red.

Important note: Red Valerian is native to Europe, North Africa and Asia Minor where it grows both in the wild and as an ornamental. In parts of North America it has escaped from cultivation and poses a threat to native eco-systems. In some of these regions it is classed as an invasive plant and should not be cultivated.

Dianthus 'Doris' (Pink)

Chalk Loving Plants, Dianthus Doris, Pink
Form:
perennial
Foliage:
evergreen
Hardiness:
UK - hardy; USDA zones 5 to 9
Soil:
thrives on chalk but will grow in any well drained soil
Situation:
sun
Height:
45cm (18in)
Spread:
30cm (12in)
Awards:
RHS AGM

Reasons to grow: Deliciously scented pink blooms over a long period from early summer to early autumn and an excellent and long lasting cut flower. One of the best flowering plants for chalk soil.

Also consider: 'Mrs Sinkins' for white flowers; 'Bovey Belle' for clove scented fuschia pink flowers.

Verbascum chaixii 'Sixteen Candles' (Mullein)

Verbascum chaixii Sixteen Candles, Mullein
Form:
perennial
Foliage:
semi-evergreen
Hardiness:
UK - hardy; USDA zones 4 to 8
Soil:
prefers chalk or alkaline soil but will grow in any well drained soil
Situation:
full sun
Height:
1m (40in)
Spread:
50cm (20in)

Reasons to grow: The attractive basal rosettes of felted grey-green leaves produce tall spikes, often multi-branched, of golden yellow flowers from June to August. Each flower has eyecatching violet stamens.

This is a excellent form and longer lived than many other types. if you deadhead after the first flowering, you will get a second flush of flowers later in the year.

Also consider: Verbascum bombyciferum for a taller plant (1.8x1m, 6x3ft) with exceptional woolly grey green foliage and pale yellow flowers; Verbascum 'Cotswold Beauty' for bold spikes of peachy pink saucer shaped flowers; Verbascum 'Helen Johnson' is a smaller plant (90x30cm, 3x1ft) with unusual pinkish brown flowers.

Climbers for Chalk Soil

Akebia quinata (Chocolate Vine)

Climbers For Chalk Soil, Akebia quinata, Chocolate Vine
Form:
climber
Foliage:
semi-evergreen
Hardiness:
UK - hardy; USDA zones 5 to 9
Soil:
any moderately fertile soil; tolerates chalk
Situation:
full sun or partial shade
Height:
10m (33ft)
Spread:
9m (30ft)

Reasons to grow: This is another of my favourite plants for chalk soil - a fast growing yet graceful climber with semi-evergreen leaves and clusters of scented purplish red flowers in late spring and early summer.

In hot summers it may produce unusual sausage shaped purple fruits.

Clematis 'Warszawska Nike'

Clematis Warszawska Nike
Form:
climber
Foliage:
deciduous
Hardiness:
UK - hardy; USDA zones 4 to 9
Soil:
thrives on chalky, alkaline soils but will grow in any well drained soil
Situation:
sunny position but with a cool shady root run
Height:
2-3m (6.5-10ft)
Spread:
1m (3ft)
Awards:
RHS AGM

Reasons to grow: Absolutely stunning large wine red flowers with contrasting yellow anthers are produced from mid summer well into autumn.

Also consider: Clematis 'Comtesse de Bouchard' for bright mid pink flowers; Clematis 'Miss Bateman' for palest pink flowers.

Need More Information?

More ideas for plants that grow in chalk soil can be found at Choosing Plants for Chalk Soil: Trees and Shrubs.

Not looking for plants for chalk soil? Links to all the 'plants for places' pages on this site can be found at plant guides.

You can find information and advice about garden soil, including links to other soil-related pages, at garden soil.