Unveiling the Secrets of your Soil: The Tale of Alkaline vs. Acidic


Most gardeners understand that their soil is the foundation on which their plants will thrive. But not all soil is the same. Some gardens are blessed with alkaline soil, while others are home to acidic soil. Understanding these differences and knowing which perennials and shrubs grow well in each type is the key to a beautiful garden. In this blog, we'll explore the unique characteristics of alkaline and acidic soil and introduce you to a diverse range of plants that will love in either type.

Alkaline Soil vs. Acidic Soil: What's the Difference?

Before we look at plant recommendations, let's first understand the basic differences between alkaline and acidic soil:

Alkaline Soil:

Acidic Soil:

Plants for Alkaline Soil:

  1. Lavender (Lavandula spp.): This is a woody perennial and will thrive in alkaline soil, highly scented so adding fragrance and colour to your garden in shades of purple, pink and white from June to August depending on the variety.
  2. Yarrow (Achillea spp.): Yarrow's feathery foliage and clusters of flat-topped flowers do well in alkaline soil, with many shades of white, pink, red, yellow and orange. Long flowering perennials and they are semi-evergreen.
  3. Russian Sage (Perovskia atriplicifolia): With its silvery-grey foliage and tall spires of purply blue flowers, Russian sage is a stunning choice for structure, colour and texture.
  4. Sedum (Sedum spp.): These succulent perennials are not only drought-tolerant but also love alkaline soil. They come in various shapes, sizes and colours. They flower in the late summer and into the autumn.
  5. Butterfly Bush (Buddleia spp.): Known for attracting pollinators, butterfly bushes thrive in alkaline soil and produce vibrant, butterfly-like blooms in many shades of purple, pink and white, also drought tolerant and require little maintenance.

Plants for Acidic Soil:

  1. Azalea (Rhododendron spp.): Azaleas are famous for their stunning, colourful blooms early in the year. They have evergreen foliage and will need to be planted in acidic soil.
  2. Magnolia Stellata: This shrub or small multi-stem tree not only loves acidic soil but also rewards you with a fabulous display of star like blossom in the Spring.
  3. Rhododendron (Rhododendron spp.): With their large, showy flowers, rhododendrons are acid-loving favourites in many gardens. A larger shrub than the Azalea but from the same family, these too are evergreen and flower early in the spring.
  4. Pieris: Interesting evergreen leaves that a long and slender and can be variegated or differing shades of green. New growth is produced in the early spring and is normally orange/red which look like a flower from afar. They do also produce flowers later in the spring/early summer.
  5. Heather (Calluna spp. and Erica spp.): These low-growing shrubs offer a carpet of tiny flowers in shades of pink, purple, white, blue and red. They will do very well in acidic soil and keep the weeds down!


Understanding the pH level of your garden’s soil is the foundation for a garden to thrive and do well. You will need to ‘feed’ your soil, no matter what the soil type is, and this will help your plants to grow and remain healthy. A good soil improver for an acidic soil is bonemeal, lime, wood ash or you’re your own compost heap. For alkaline soil use compost or well-rotted horse manure, or an improver called 6X available from most garden centres.

Whether you have alkaline or acidic soil, there's a wide selection of perennials (plants that die down in the winter, only to reappear in the spring) and shrubs (woody stem plants that can grow quite big if not cut back or shaped) that will flourish in your garden. To find out your soil’s characteristics you can visit www.landis.org.uk/soilscapes/ and input your postcode, then you can start planning your plant list and planting scheme. With the right plants and plant combinations, your garden can look amazing all year round.

Look out for my blog, ‘Right Plant, Right Place: Planting Combinations for all areas of your garden’.

Happy gardening!

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