Growing herbs and salads in a windowbox provides a fresh supply close to the kitchen, and by making a box to your own specifications, you can ensure it fits your space perfectly. All you need are some simple tools and a few basic carpentry skills to create this design.

When to start: Any time.

At their best: Spring and summer.

Time to complete: 4 hours.

You will need: Herbs and small lettuce plants, drill, saw, tape measure, 2 in (5 cm) self-tapping screws, treated lumber, battens (about ½ in thick), copper antislug tape, ½ in (12mm) roofing tacks, multipurpose compost.

Measure wood

Decide on the length of your windowbox and buy pieces of wood long enough to make two sides, two ends, and a base, and mark them out.

Cut into lengths

Double-check the measurements and cut out the pieces. To create straight cuts and a neater finish, support both ends of the lumber as you saw.

Screw sides together

Use self-tapping screws to attach one side piece to an end piece; two screws should be enough. If the wood is hard, drill small pilot holes first. Repeat with the other side and end pieces. Screw the two sections together.

Attach battens to base

Attach the base by screwing it to both side and end pieces. Cut two battens to size, to fit the underside of the box. These will lift the base off the windowsill, allowing space for drainage. Turn the box upside down and attach the battens with short screws.

Drill drainage holes

Good drainage is essential for healthy plants. With the box still upside down, use a drill to make a ½ in (1 cm) hole every 4 in (10 cm) along the base of the trough. Take care not to damage the surface below.

Fix copper tape

Attach a band of copper tape around the trough to deter snails and slugs, and to provide a decorative finish. Check that you have sufficient tape to wrap all the way around without leaving any gaps.

Nail tape securely

To keep the tape in place, hammer small tacks along it, at 4–6 in (10–15 cm) intervals. Add more to make a feature of them, if desired. Make sure the tape seam is secure. Plant with herbs and salad leaves Fill the trough with compost and plant up with a range of herbs, and a few young lettuce plants. Make sure none of them forms a bridge over the copper tape as they grow, which would enable snails to bypass the tape and climb in.