Why autumn is the best time to give your tent some love

If you've spent the summer at festivals, campsites and family gatherings, your tent has probably earned a rest. The trouble is that tents don't rest well when they're shoved into a cupboard still carrying grit from a wet weekend in the Peak District. Left damp, modern fabrics and coatings can brew mildew within a fortnight, and once black spots take hold in a groundsheet they never truly come out.

The good news is that a proper clean and check takes an afternoon, not a weekend. Pick a dry, still day in early autumn while there's still warmth in the sun, pitch the tent in the garden or on a clean patio, and work through the steps below. Do that and your tent will be ready for next spring rather than needing replacing.

Cleaning mud and grime without damaging the fabric

Never put a tent in the washing machine and never take a pressure washer to it. Both strip the water-repellent finish and can tear stitching. Instead, work by hand.

• Shake out loose dirt and grass first, inside and out, then sweep the groundsheet with a soft brush.
• Fill a bucket with lukewarm water — no hotter than you'd use on a baby's bath — and add a small amount of pure soap flakes or a gentle non-detergent cleaner. Biological washing powder, fabric conditioner and household multi-surface sprays are all off-limits.
• Sponge the mud away rather than scrubbing. For dried-on patches, let the water soak for a few minutes, then wipe with a soft cloth.
• Pay attention to the zip flaps, the pole sleeves and the inside of the groundsheet, where grit collects and wears away the coating.
• Rinse thoroughly with clean water. Soap residue left in the fabric actually attracts moisture and can encourage mould.

If you've been at a festival and the flysheet smells of woodsmoke, a rinse in cool water usually sorts it. Avoid leaving the tent soaking in a bucket — fifteen minutes is plenty.

Reproofing the flysheet and sealing the seams

Water beading on the flysheet is a sign the durable water repellent finish is still working. If water soaks in and the fabric darkens, it's time to reproof. You can also test by holding the flysheet taut and pouring a little water on it — if it wets out within a minute, treat it.

Clean and dry the tent completely first, then choose a proofer that matches the fabric. Silicone-treated flysheets need a silicone-based proofer; polyurethane-coated fabrics suit a water-based one. Spray-on proofers are easiest for large panels and give a more even finish, while wash-in products can leave the fabric feeling slightly tacky if over-applied.

• Work in the shade, in the open air, and wear gloves.
• Spray from about 20cm, in overlapping passes, then wipe any excess with a clean cloth.
• Let it cure for at least 12 hours before packing, ideally somewhere airy and out of direct sunlight.
• Check the seams along the ridge and the corners. If the tape is lifting, a thin bead of seam sealant on the outside will stop drips creeping in.

Avoid reproofing the groundsheet with the same product — it needs grip, not slipperiness, and a separate waterproofing treatment is a better match.

Poles, pegs and zips: the hardware check

Fabric gets the attention, but the hardware is what fails at 11pm in horizontal rain. Run your fingers along each pole section, feeling for dents, hairline cracks and splinters. Pay special attention to the ferrules — the metal sleeves that join the sections — as these take the strain in wind. A cracked ferrule can be replaced cheaply, and it's far easier to do at home than to improvise with gaffer tape in a field.

Check the shock cord too. If it's slack and the pole sections flop apart, the cord needs replacing; it's a simple job with a length of 3mm elastic and a few minutes' patience. Straighten aluminium pegs, bin the rusty ones and replace any that have bent more than once.

For zips, brush out grit with an old toothbrush, then run a silicone zip lubricant or a little beeswax along the teeth. Don't use oil — it attracts dust and stains the fabric. If a zip slider has started skipping, squeezing it gently with pliers often restores the grip.

Drying, folding and storing for winter

A tent must be bone dry before it goes away. Any moisture sealed inside will turn into mildew over winter, and that smell is almost impossible to remove. Pitch it one final time on a dry, breezy day, or drape it over a washing line in the shade, and let it air inside and out.

Store it loosely rather than compressed. The stuff sack is for travel, not for months in a cupboard. A cotton pillowcase, a cardboard box or a large mesh bag lets air circulate and avoids sharp creases in the coating. Keep it somewhere cool, dark and dry — a spare room or a high shelf beats a damp garage or a loft where mice and extreme heat do their worst. Never leave it in the boot of a car for weeks.

Small repairs now save big ones later

Before you put the tent away, deal with the little things. Patch pinholes in the groundsheet with a self-adhesive repair patch, and reinforce any stitch lines that have started to pull. Replace missing guy lines and check the tensioners still grip. If you find mildew spots, wipe them with a diluted white vinegar solution, rinse and dry in gentle sun before storing.

Half an hour of care in September buys you seasons of reliable shelter. When the first festival of next summer arrives, you'll be pitching a dry, fresh-smelling, properly proofed tent while everyone else is hunting for a replacement in the queue.