Ask the Plant Doctor! How to apply fertiliser in rainy weather

Instead of applying a single large dose of fertiliser, split the application into smaller but more frequent doses. Photo: 123rf.com

Do you have a question about plants or how to maintain your garden? Send your questions to the Plant Doctor! Email your questions to [e-mail] with "Plant Doctor" in the subject field. Questions may be edited for brevity and clarity.

Dear Plant Doctor,

During rainy weather, what is the best way to apply fertiliser to my plants in the home garden? – Samantha L.

Select slow-release or controlled-release fertilisers. They are designed to release nutrients over an extended period, rather than all at once, which significantly reduces the risk of nutrient loss through leaching or runoff during heavy rain.

Choose solid granular fertilisers over liquid forms, as liquids are more susceptible to being washed away by rain.

Incorporating fertilisers directly into the soil rather than scattering (broadcasting) them over the surface can also help to minimise losses due to runoffs.

This method should be performed carefully to avoid excessive soil disturbance that can cause erosion.

Additionally, instead of applying a single large dose of fertiliser, split the application into smaller but more frequent doses. Applying many small doses can reduce the risk of nutrient loss, particularly during heavy rainfall periods.

Monitor weather forecasts to fertilise only when a break in heavy rain is expected. Applying fertiliser just before light or moderate rain can aid in transporting nutrients into the soil; however, it is important to avoid fertilisation before heavy downpours to prevent the removal of nutrients.

Conducting a soil test is essential for understanding the specific nutrient needs of a garden. This knowledge allows the application of only the necessary amount of fertiliser, thereby reducing the likelihood of excess nutrients being lost under wet conditions.

The establishment of buffer strips, such as planting grass or other low-growing vegetation around the perimeter of a garden, can effectively trap and absorb stray nutrients. In addition, they never leave the garden soil bare.

Covering exposed soil with cover crops, such as grass or other short vegetation, not only helps retain soil nutrients, but also protects against water erosion. This approach not only nurtures your garden but also contributes to the broader health of the garden ecosystem.