Preparing Indoor Plants for a Summer Holiday

Before You Go: Give Everything a Proper Drink

The single most useful thing you can do for your houseplants before a holiday is to water them thoroughly the day before you leave — not the morning you go, and certainly not in a rushed five minutes with the taxi waiting. A deep, slow soak gives the compost time to absorb properly and lets any excess drain away, so you are not sending your plants off with soggy roots sitting in a stagnant saucer.

Stand each pot in a basin of water for twenty minutes or so, or water from the top in two or three gentle passes, waiting for the surface to darken between each one. Then let them drain completely. If you water the morning you leave, a surprising amount simply runs down the inside of the pot and out of the bottom without ever reaching the roots.

While you are at it, check which plants actually want a drink. Succulents, cacti, snake plants and ZZ plants will happily go three weeks dry in a British summer and will rot if you pamper them. Ferns, calatheas, peace lilies and spider plants are the thirsty ones who need your attention.

Set Up Self-Watering That Genuinely Works

Shop-bought water spikes and glass globes are fine for a long weekend, but they are unreliable over a fortnight. The homemade versions tend to behave better, because you can size them to the plant.

• Wick watering: cut a strip of old cotton towel or thick string, push one end an inch into the compost and dangle the other into a jug of water placed slightly higher than the pot. Water travels up by capillary action. Test it for a day before you go.
• Capillary matting: line a washing-up bowl or the bath with capillary matting, sit the pots on top and pour water into the tray until the mat is soaked but not flooded. The mat stays damp and the compost draws up what it needs.
• Bottle reservoirs: fill a plastic bottle with water, prick two small holes in the lid, and push it upside down into the compost so the lid sits just below the surface.
• Self-watering pots: if your plants already live in them, simply fill the reservoir to the maximum mark and top it up once more before you lock the door.

Whatever you choose, set it up a week in advance. A wick that has dried out or a mat that is not touching the pot base will do nothing at all, and you will only discover this too late.

Shade the Delicate Leaves, Reposition the Sun-Lovers

A British heatwave can push a south-facing windowsill past 40°C, and a fortnight of unfiltered midday sun will scorch the leaves of ferns, calatheas, peace lilies and most young foliage. Move anything tender back from the glass, or shift it to an east-facing spot that catches only morning sun.

If you cannot move a large plant, rig up some shade with a sheet of newspaper or a light cotton cloth taped loosely across the window. It looks untidy for a fortnight and saves a year of regrowth.

Meanwhile, move your sun-worshippers — jade plants, aloes, cacti, string of pearls — right into the brightest spot you have. They will relish the light and the dry spell, and you will come home to noticeably firmer growth rather than a pale, stretched plant.

One more thing: close the curtains in rooms you are not using, and pull blinds down during the hottest part of the day. The cooler the room, the slower the plants use water.

Group Plants Together to Build a Humid Microclimate

Plants clustered together create their own little atmosphere. Each leaf releases moisture, and in a tight group that moisture lingers rather than drifting off into a dry room. The result is higher humidity around the foliage and slower evaporation from the compost — two benefits for the price of one.

Push your tropical plants into a rough circle, leaving a small gap between pots so air can still move and mould does not set in. Stand them on a large tray of gravel with a centimetre of water in the bottom, making sure the pots sit on the gravel rather than in the water.

Bathrooms and kitchens are often the most humid rooms in a British home, so if you have room and decent light, a fortnight in the bathroom is no hardship for a Boston fern or a parlour palm. Just check the light levels first — a windowless bathroom will do more harm than good.

Tidy, Check for Pests and Mulch the Surface

Before you go, remove any yellowing or dying leaves. They will only rot in the warmth and give fungus a foothold. Give each plant a proper look underneath the leaves and along the stems — greenfly, mealybugs, red spider mite and scale all spread fast in summer heat, and a fortnight unattended is a fortnight of unchecked breeding. Wipe anything suspicious away with a damp cloth.

Then cover the surface of the compost with a centimetre of gravel, bark chips or even a piece of damp newspaper. This mulch slows evaporation considerably and stops fungus gnats from settling in while you are away.

Move plants off radiators and away from draughty doorways, and make sure none are standing in saucers of standing water for more than an hour after their final soak.

Coming Home and Easing Back Into Routine

When you walk back through the door, resist the urge to drown everything. Check the compost an inch below the surface first, and water only what is genuinely dry. Most plants will look a little tired, perhaps with a few curled leaves, and will perk up within a few days.

Trim off anything brown and crisp, resume your normal watering rhythm gradually, and hold off feeding for a fortnight — a plant recovering from drought will not thank you for a sudden surge of nutrients. Within a week or two, your green corner will be as settled as you are.