I often feel I should go on holiday in deepest, darkest winter, when even the weeds are having a break. Despite my strong environmental credentials, I confess to a constant battle removing moles, fending off slugs and preventing thuggish plants from overwhelming my large garden.

During July, you might be facing the same problems as I do with weeds. In fertile garden soil weeds usually grow fatter and faster than the plants we want, smothering neighbours and denying them light, nutrients and moisture. They may harbour pests and disease that could spread to our crops.

So, either before going on holiday or on your return, what weeds should you concentrate on if you don’t have time to do the entire garden?

Start weeding the more vulnerable vegetable beds. Onions and leeks grow much more slowly than courgettes. And, unlike squash with vast plate-like leaves, their thin, upright stems are easily overwhelmed by weedy neighbours. There’s some evidence that competition for nutrients from weeds can reduce the harvest by 4 per cent per day.

Recently sown beetroot, turnips, carrots or parsnips may also need some attention, as they will grow more slowly than weeds. But these roots should be safe if you used a stale seed bed for the crop. (This involves preparing the ground two or three weeks before sowing, allowing weeds to germinate then hoeing off the flush of seedlings, disturbing the soil as little as possible. Then your seed will have stolen a march on any rivals.)

Larger plants, such as peas, broad beans and potatoes, can hold their own against a lot of weeds. They may benefit from the moisture-retaining ground cover provided by chickweeds, which also helps exclude light from developing tattie tubers, thereby reducing the risk of getting green, poisonous potatoes.

Unlike most perennial vegetables, asparagus needs careful cosseting at this time of year. The plants spend most of the summer recharging their crowns for next year's feast, so need absolutely no competition for nutrients. I’m all too happy to lovingly hand weed that bed.

But large-leaved perennials, such as globe and Jerusalem artichokes, can be left to look after themselves. No impertinent weed would dare grow close to them. And well-established brassicas, such as autumn broccoli, are pretty safe.

You don’t need to worry about any recent transplants. They’ll have a head start on newly germinating weeds, especially if you’ve been growing them in homemade compost.

Depending on the type of weeds, you may have to modify these general principles. Some species cause more damage and are a greater threat to crops than others.

A yellow carpet of lesser celandine looks fetching in the spring, but it’s a speedy spreader and is hard to eradicate. The plant grows from tiny bulbs which survive the composting process, so it’s one of the very few species I’d consign to the dustbin.

Other weeds, such as ground elder and buttercups, store nutrients in their rapidly-spreading root systems. You’re doomed to a lengthy battle with them, but constant weeding should help win the war.

Couch grass not only "steals" nutrients but also emits an allelopathic chemical that prevents nearby seeds germinating and stunts growth. It should certainly be the weeder’s main target, wherever it grows.

Weeds about to flower are bad news anywhere in the garden. One chickweed plant can produce up to 15,000 seeds. And others, like dockens, can persist in the soil for more than 50 years. So, consign them to the compost heap before they flower.

Hoeing is the easiest way of keeping the garden weed-free. But it only works during dry weather, when a decapitated weed quickly shrivels in the sun. In wet conditions, you only disturb the weeds. This slows them down, so gives some breathing space before your holiday or time to get round everything when you get back. Otherwise, it’s the bucket and trowel.