How to water containers

Don't worry if you're new to container gardening and not sure how often or how much you'll need to water. If you follow the steps below, checking moisture levels regularly, you will quickly be in tune with the needs of your plants.

• Plan to water early morning or early evening. Watering pots at the cooler times of day reduces the amount of water evaporating from the compost
  Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own. surface, meaning more is available to plant roots.

• Check the moisture level of each container before you water. Use your finger to feel the moisture level at about a third of the way down the pot. If it’s dry at that depth, then watering is needed. Remember, plants use and lose more water in warm, windy weather. Light rain and short showers are unlikely to wet the compost more than a few centimetres down, so watering may still be needed even if it has rained recently.

• Fill your watering can to a manageable weight. It’s better for your back to do more trips with a lighter weight than struggle with a heavy can.

• Water slowly and thoroughly to soak the compost. Pour on enough water to fill up to the rim of the pot and let that soak in before repeating once more. Watering slowly, close to the compost, avoids disturbance and limits runoff.

• Water the compost, not the foliage. This helps to avoid spreading fungal diseases, such as rose black spot. Water intercepted by the foliage also means less reaches the roots.

• Stop watering before it runs out of the bottom of the pot. Completely saturating the compost isn't necessary; it wastes water and washes nutrients
  To grow well, plants need a wide range of nutrients in various amounts, depending on the individual plant and its stage of growth. The three key nutrients usually taken up from the soil are nitrogen, phosphorus and potassium. Plants also need carbon, oxygen and hydrogen to make carbohydrates — their main energy source. Carbon and oxygen come from the air as carbon dioxide, while hydrogen is drawn from water absorbed by the roots. Other important soil nutrients include magnesium, calcium and sulphur. Most garden soils contain enough of these nutrients to support healthy plant growth. away. Aim to stop just before, or as soon as, you see water coming from drainage holes.

There is no fixed schedule, but in summer dry spells, you may well need to water every day or every other day. See our guide to growing plants in containers for more information.

To help you prioritise your plants' watering needs, bear in mind that:

• Young and newly planted plants need watering regularly (sometimes daily) in warm, dry weather
• Drought tolerant plants, like those with small, fleshy or silvery leaves, can be left longer between waterings
• Larger/deeper pots hold moisture longer than shallow ones
• Terracotta pots dry out quickly and metal ones heat up in the sunshine, baking the compost
  Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own. inside
• Containers in north- and east-facing positions generally don’t dry out as quickly as those in south- and west-facing positions
• Evergreen plants in containers may need watering during dry spells in winter
• It is best to water well when needed, rather than just little and often

 Other simple ways to save water:

• Dunk small pots into a bucket or tub of water
• Use grey water on established, ornamental container plants
• If you’re off on holiday, consider using a self-watering system

If you’ve previously gardened with peat‑based compost, you may find that peat‑free compost needs watering a little less heavily but slightly more often. Use the steps above, along with our tips on working with peat‑free compost, to judge when your container needs watering.

• Group plants together to raise the local air humidity
  The concentration of water vapour in the atmosphere. This affects the rate at which plants transpire (lose water from their leaf pores), which in turn affects how much water their roots absorb from the soil. If air humidity is low, plants transpire quickly and become at risk of wilting if water is lost from the leaves faster than it can be absorbed by the roots. Different plants require different levels of humidity to thrive. Many tropical houseplants need high humidity and are best grown in a steamy bathroom, misted regularly or placed on a saucer of damp pebbles. In a greenhouse, humidity can be raised in hot weather by damping down (wetting) the floor or overhead misting. . Foliage shading the compost
  Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own. surface will help reduce evaporation
• Mulch
  Mulch is a layer of material, at least 5cm (2in) thick, applied to the soil surface in late autumn to late winter (Nov-Feb). It is used to provide frost protection, improve plant growth by adding nutrients or increasing organic matter content, reducing water loss from the soil, for decorative purposes and suppressing weeds. Examples include well-rotted garden compost and manure, chipped bark, gravel, grit and slate chippings. with a layer of garden compost, chipped bark
  Bark is the outermost layer of woody plants (trees, shrubs and woody climbers). It is several cells thick and provides protection against physical damage, disease and environmental stresses. Bark comes in a wide variety of colours and patterns, and these can help gardeners when identifying plants. The fissures and crevices of bark on older plants also creates valuable habitat for many garden creatures as well as lichens and small plants. or gravel to slow moisture loss
• If feasible, position containers near your water butt of stored rainwater to save time and energy
• In summer, place saucers or trays under containers to catch runoff, but empty them a few hours after watering to prevent the compost becoming completely saturated. Remove them completely over winter
• During very dry, hot spells, move containers to a shadier position to reduce moisture loss