Perennials for chalky soil
Chalky soils are alkaline, free draining and ‘thin’, making them susceptible to drying out in the summer. Lots of perennials will succeed on chalk and by following some simple planting steps, chalky soil should not stop you growing a beautiful perennial flower garden. The best perennials for chalk are Achillea, Agapanthus, Anemone, Aster, Campanula, Crocosmia, Delphinium, Foxglove, Echinacea, Eryngium, Euphorbia, Geranium, Geum, Hellebore, Hemerocallis, Heuchera, Hosta, Iris, Kniphofia, Monarda, Penstemon, Peony, Poppy, Rudbeckia, Salvia, Sedum and Veronica. We would recommend establishing how deep the soil is above the chalk before planting. If the depth of top soil in your garden is particularly shallow (some may have just 10cm or a few inches of soil before hitting solid chalk), additional top soil may need to be added on top of your ground to make planting viable. If your topsoil is deeper or the chalk can be broken up, break up larger lumps and incorporate plenty of well rotted organic matter to both improve the moisture retention of your soil and provide space for the roots of your perennials to spread out into as they establish. It’s particularly important to water plants until they’ve become established if you’re growing on chalk given it is more prone to drying out.