Hanging baskets are one of the great joys of a British summer, brimming with trailing lobelia, busy lizzies and fuchsias. But they are also one of the thirstiest things in the garden. A basket packed with plants has a tiny volume of compost, is exposed to wind and sun on all sides, and can dry out in a matter of hours on a hot day. Get your watering right, though, and your baskets will reward you with colour right through to the first frosts. Here are some practical tips to keep them looking their best.

Why Hanging Baskets Dry Out So Quickly

Unlike a border or a large container, a hanging basket has very little compost to hold moisture. The plants quickly fill that space with roots, and on a warm, breezy day, water evaporates from the leaves and compost at an alarming rate. A basket that felt heavy at breakfast can be surprisingly light by mid-afternoon. Wind is often the biggest culprit – it strips moisture from foliage faster than strong sun alone. Add in the fact that many baskets are hung against a south-facing wall, which radiates heat back onto the plants, and you can see why they need close attention. Even a generous 35cm basket can need watering twice a day in a heatwave.

Check Your Baskets Morning and Evening

Make a habit of checking your baskets at least twice a day in summer: once in the morning and again in the evening. In the morning, you are setting them up for the day ahead. In the evening, you are topping up after the heat has taken its toll. Do not simply water on a fixed schedule – check first. The simplest test is to lift the basket. If it feels light, it needs water. You can also push a finger into the compost up to the first knuckle; if it feels dry at that depth, water. Wilting is a late sign – by then the plants are already stressed. A basket that is dry but not yet wilting is your cue to act. If you are going out for the day, move baskets to a cooler spot before you leave.

Soak Until Water Runs Free

Little and often is the worst way to water a hanging basket. A quick splash only wets the surface, encouraging roots to stay near the top where they bake. Instead, water thoroughly until water runs freely from the drainage holes. Use a watering can with a rose attachment to avoid blasting the compost out of the basket. If the compost has become very dry, it can turn hydrophobic and repel water. In that case, water once, wait ten minutes, then water again. For a really parched basket, take it down and plunge the whole thing into a bucket of water for fifteen minutes, then let it drain before rehanging. This rehydrates the compost evenly. Always let the basket drain properly – sitting in a puddle will rot the roots.

Move Baskets Out of the Scorching Midday Sun

Even sun-loving plants such as petunias and geraniums can struggle when their roots are cooked. During a heatwave, move your baskets out of the fiercest midday sun. A spot that gets morning sun and afternoon shade is ideal. If you cannot move the bracket, try turning the basket regularly so all sides get a break, or rig up a temporary shade cloth. A parasol or a piece of old net curtain can work wonders. The goal is to reduce rapid drying without plunging the plants into deep gloom – most flowering basket plants still need several hours of good light. If you are planning ahead, choose a hanging position that gets shelter from the hottest part of the day, such as an east-facing wall.

Fine-Tune Your Watering Routine

A few extra habits will make a big difference. Group baskets together so they create their own humid microclimate. Add a mulch of gravel or bark chips to the surface of the compost to slow evaporation. When planting, mix in water-retaining gel crystals – they act as a reservoir. Feed your baskets regularly, because frequent watering washes nutrients out of the compost. A high-potash tomato feed once a week will keep flowers coming. Collect rainwater if you can; it is free and better for plants than hard tap water. Finally, avoid watering in the heat of the day. Early morning is best, as it gives plants time to take up water before the sun hits. Early evening is the second-best time, but try not to soak the foliage just before nightfall, as that can encourage mildew.

Troubleshooting Common Watering Problems

• Compost is sodden and smells sour: you are overwatering. Let the basket dry out slightly and check drainage holes are not blocked.
• Plants wilt despite daily watering: the compost may have become hydrophobic, or the basket is root-bound. Try the dunking method, or repot into a larger basket with fresh compost.
• Leaves are yellow and falling: often a sign of inconsistent watering – either too dry or waterlogged. Feel the compost before acting.
• Basket dries out within hours: it is probably too small for the number of plants. Next season, use a larger basket or fewer plants.
• Flowers drop in midsummer: heat stress and irregular watering are common causes. Move to shade and water more consistently.

With a little vigilance, your hanging baskets will stay lush and flower-filled all summer long. The secret is simple: check them morning and evening, soak them properly, and give them a break from the most brutal sun. Your neighbours will wonder how you do it.