Q&A: Green pest and weed control

Common questions answered about greener ways to control weeds and pests.

My garden is swamped with slugs and snails. I’ve tried things like bran and crunchy seashells but they don’t work. What are the alternatives to slug pellets?

Chemical-free solutions include coarsely textured material like gravel or crushed seashells instead. Simply sprinkle a thick layer around each plant.

Slugs also don’t like bran or salty things like seaweed, as they cause them to dehydrate and die.

If these don’t work, try copper slug rings. Place one around the base of each plant. They work like this: slug tries to climb the copper band, slug gets an ‘electrical charge’ from the copper, slug peels off in disgust!

Make sure the band remains in contact with the soil (or slugs sneak underneath) and remove lower leaves that drop over the band to the soil beyond.

Buy copper slug tape from Dobbies.

I’m constantly weeding my beds and borders. How can I lessen the workload without using weed killers?

First, give those borders your best-ever weed! Then lay down a ‘mulch’ or surface covering to help stop them coming back.

Mulching locks in moisture during dry spells and keeps cold clay soils warmer for longer. Organic mulches feed the soil too, and help maintain good soil structure.

Garden compost, horse manure, leaf mould, plastic, gravel and even old carpet will do (if it blends in!). Apply about 6cm/2inches every autumn to insulate the soil over winter and, if necessary, top up in early spring before most annual weeds germinate. The downside of mulching is that bulbs don’t like it and you won’t get much self-seeding of beautiful annuals like love-in-a-mist.

Another solution is to crowd weeds out with ground cover plants that behave like weeds in that they cover every inch of spare earth quickly. The only difference is you chose them!

Can you suggest a pretty, pest-resistant flowering shrub for my (trying to be) organic garden?

Lavender is a great idea. It’s a tough, robust, disease-free beauty that has loads to offer – handsome flowers, stimulating scent and attractive form.

It's also a favourite with bees and butterflies, both of which flock to the flowers throughout mid-late summer.

But its qualities don't end there. The strong smell is hated by troublesome pests like blackfly and whitefly. So plant it in clumps throughout the garden to help keep it pest-free.

I dug weeds up rather than using weedkiller. What shall I do with them now?

Annual weeds are safe to compost along with other garden and kitchen waste.

Fresh perennial weeds often have parts that can re-generate so are best kept separate. Mix them with cut grass, put in a plastic sack and leave for several months. Once they’re no longer recognisable, add them to the compost heap.

Some tiny insects live in my pot plants and other ones infest my garden. Any tips?

Use an environmentally friendly natural predator. There are many available for indoors and outdoors.
Encarsia formosa is a tiny wasp that hunts whitefly, for instance, and Phytoseiulus is a predatory mite that clobbers red spider mite. Once the pest has been eradicated, the predator – without any food – will die.

Companion planting is another solution – see our tips on greener gardening.

Another option is to attract ladybirds, bees and butterflies to your garden on their travels. Again, sites like Dobbies can sell you feeders and habitats.