Why standard compost causes problems after repotting

The same drama follows every repotting, even though everything was done “properly” – until one product was thrown out of the garden trolley.

Many amateur gardeners will recognise the pattern: new compost, fresh pots and high hopes – then, a few weeks later, the leaves are drooping limply. It is easy to blame a lack of skill, incorrect watering or “difficult” plants. Yet the real problem is often a standard item from the gardening aisle that nearly everyone adds to their trolley without a second thought.

The problem in the bag: why standard compost harms so many plants

In spring, DIY stores display veritable walls of colourful compost bags. Most prominently claim to be suitable “for all plants”. It seems convenient, inexpensive and supposedly dependable. However, that convenience can prove costly.

One substrate can never meet the needs of an indoor palm, tomato, orchid and cactus at the same time.

Typical “all-purpose compost” is a compromise. It is generally made from peat or a peat substitute, some compost and shredded bark. Although this works well for manufacturers, it can be problematic for plants. Each species requires something different:

Different plants need different compost

• some prefer acidic conditions, while others need lime