Mulch rocks my world. In fact, you find in nature that ecosystems almost always have a mulch layer over the soil surface. However for some reason, this obvious practice is often underutilised when people grow food. Mulching is the practice of applying a protective layer on the soil surface. It’s usually made of decomposable organic materials and is a must in an organic garden as it helps to conserve soil moisture and improve fertility as well as supressing weed growth and preventing soil erosion.

Organic mulches are preferable as they enrich the soil as they decompose. In the past I’ve found that ideal materials are compost, straw, leaf mould, mushroom compost or other spent plant matter. At Growhampton we love to grow our own mulch and we use either a green manure or previous crop residues.

In the early spring we grew some lovely baby spinach which produced bountifully. With all the hot weather it did eventually give up and bolted to seed. I pulled up them up and lay them as a mulch on some other beds. I also grew an early spring green manure of field pea while I propagated some cherry tomatoes in the campus polytunnel. Once the tomatoes were ready to be transplanted, I cut the field pea down and left it on the soil surface and planted the cherry tomatoes directly into this mulch layer – worked a treat.

If you make the extra effort at the start of the crop cycle and mulch heavily, you can save yourself an endless amount of time with watering through the season, which also helps cut down how much water you’ll use as well. The best time to water crops is early in morning, before the sun gets too hot, or alternatively later in the afternoon when it cools down. If it’s inescapable and you must water in the middle of the day, take care not to wet the leaves as this can burn them if they’re exposed to hot sun and wet leaves through the cooler evenings can encourage disease.

Next week I’ll be talking about growing radishes and showing you how much fun pupils from the Alton school had when they planted their own radish seeds.


Joel Williams is the Grower for the University of Roehampton Students’ Union’s Growhampton project

Top Tip for the week: Mulch lightly between rows as soon as young seedlings emerge, being careful as you apply. An early mulch application will help seedlings establish themselves and encourage better root development into the inter-row areas.