There is no wrong substrate, each soil hosts a different plant palette. The limestone soil is famous for being draining, light, even poor and stony.
Find out which plants do well in alkaline soil and how to improve it!
Read also :
- Know the type of soil in your garden
Know the pH of my soil
The pH of the soil is measured on a scale of 1 to 14. From 1 to 7, soil is called acid, that is, chemically speaking, it contains a lot of hydrogen cations (H +). Around 7, it is considered neutral. Between 7 and 14, it is a basic soil, also called alkaline or limestone.
Don't know the pH of your garden soil?
- You just need to take a little substrate at a depth of 3cm.
- Place this extract in a small container and add pH neutral water such as Volvic.
- Mix well and let the soil fall to the bottom of the container.
- Then, dip a drugstore-bought test strip and observe the result.
- If your field is large, feel free to take several tests.
Shrubs for calcareous soil
Abelias are among the shrubs that thrive in chalky terrain. Often used as a hedge, they offer foliage in various colors depending on the variety chosen. Some are variegated with cream or pink, others are green, and sometimes the leaves are tinged with purple. Added to this is a beautiful, fragrant bloom that lasts from June to October, white or pink depending on the cultivar.
Resistant down to -10 ° C, this shrub appreciates light, well-drained or even poor soils.
Euonymus japonicus, from its Latin name. A beautiful shrub which fulfills its role well thanks to a compact habit, oval and evergreen leaves. Tolerating temperatures down to -15 ° C, it is suitable both in the ground and in vats where its development will be more moderate.
The charcoals are distinguished by decorative foliage! The 'Aureus' variety has green leaves variegated with golden yellow. Also in the yellows, the dwarf cultivar ‘Hapiness’ offers shoots with the upper half sporting a bright yellow. Some varieties tend towards white, such as the 'Pierrolino' charcoal with white speckled leaves or the 'Suzanne' variety with its discreet white border on its foliage.
Perennial plants for calcareous soil
For your limestone beds, bet on three purple flowers! The aubriète whose evergreen leaves are rattled by small single purple flowers with four petals in spring. The bluebells, whose mauve flowers are sometimes like bells, sometimes like trumpets.
Then lavender, whose more or less fluttering floral spikes smell of Provence. These three perennials appreciate the sun, dry, well-drained, light, even poor and stony soil.
Do not hesitate to combine them with sage and santolina, including the gray-silver foliage go perfectly with these purple shades. In addition, these two perennials have the same requirements as our flowering trio.
Plants for limestone soils in the shade
It is true that many calcareous soil plants also appreciate a sunny exposure and a dry and drained substrate. However, there are alkaline-loving plants that do well in shade. This is the case with the acanthus, this large perennial with huge white and purple floral spikes!
We also think of the Corsican hellebore and its green flowers and the Pinot noir ’euchère and its purple leaves.
Among the shrubs, we can count on the arbor and the common privet, which form low hedges and well-trimmed borders.
We accompany them witha syringe white and its crumpled bloom in June-July and a white snowberry, whose round pearly berries are on display from fall to winter.
How to correct a limestone soil?
Acidify a calcareous soil
Are your dreams populated by hydrangeas, camellias and rhododendrons? The heather earth plants that love acidic substrates are eye-catching. You can still plant them in pots, most garden plants grow well in containers or have dwarf varieties. However, it is also possible to make your soil more acidic. To do this, it must be enriched with organic matter such as compost or pine needles, leaf mold and liquid manure. You can also add sulfur or iron sulfate.
Improve limestone soil
It is best, however, to take advantage of the beautiful plants that a limestone soil offers. Indeed, acidifying the soil is ephemeral and this chemistry work requires regular efforts. Plants thrive and look beautiful in an environment that really suits them.
Instead, be content with adding organic matter and sowing green manures to expand your plant range a little and ensure good harvests in the vegetable garden. You will not end up with an acidic substrate but a richer calcareous soil which holds more nutrients and water.