Alkaline soil is usually limey or chalky and often stoney and can be a challenge for gardeners that grow in this often free draining soil that is not very nutrient rich but there is a vast array of beautiful alkaline loving plants such as Helianthemum, Dianthus and showy Delphiniums to name but a few that thrive in this soil type. If you want to try to lower the PH level of the soil large quantities of organic material may help but long term could prove a waste of time and to change a whole garden would prove an impossible task, raised beds with good quality topsoil could be an alternative if you want to grow acid loving plants. If acidic loving plants are planted in alkaline soil the result would be poor growth and yellow leaves and they would look very sick indeed. The soils ph can be altered if it is one or two acid loving plants you are wanting to grow by adding chemical compounds to acidify the soil. There are many products available on the market sulphate of iron is a common acidifying compound along withe aluminium sulphate these usually come in powder form and are added to the soil. It is possible to grow a variety of acid loving plants in pots and containers using ericaceous compost if your soil is to alkaline. When the plants are fed ensure you use an ericaceous plant food a liquid feed is ideal and easy to use for all container grown plants.
Below is a list of plants that are suitable for gardens with alkaline soil...