Container maintenance

Growing plants in containers is a great way to bring life and colour into otherwise dull spots in your garden. Patios, balconies and window boxes are all places where plants can be easily introduced in containers. Plants in containers do require more care than those in gardens, but by following our advice you will find this easy.

You can grow a wide range of plants in containers. Image: Neil Hepworth/RHS

Quick facts

Suitable for All plants grown in pots, troughs and other containers
Timing All year, but mainly from mid-spring until early autumn
Difficulty Moderate

Plants for containers

Almost any type of plant can be grown in a container. Generally, the bigger the pot and the plant, the easier it is to care for. Soft, fleshy, leafy plants such as tomatoes and fuchsias are more demanding than ‘leathery’ plants such as pelargoniums (tender geraniums) or lavender.

For more on ideas of plants to grow in containers, see the links below;

Lilies: growing in containers
Roses: growing in containers
Trees: growing in containers
Fruit in containers
Herbs in containers
Vegetables in containers

General maintenance


Plant in early spring so that plants quickly put out roots and become established. Autumn planting may lead to losses from waterlogging and evergreens may deteriorate over winter from dryness at the roots or wind-burn of the foliage.


Watering is one of the most important jobs when growing plants in containers. Not enough water will cause plants to dry out, and maybe die. On the other hand, overwatering is very damaging as most plants do not like sitting in water. See the advice below on summer care and winter care for information on watering plants in containers.


See the advice below on summer care and winter care for information on feeding plants in containers.


Plant roots eventually fill containers and this often reduces growth. This is not necessarily a bad thing as slightly stressed plants are often attractive and the slower growth reduces the maintenance needed. However, eventually the plant will need to be moved to a bigger container or the compost refreshed in the same pot, as composts lose their structure over time. Shrubs and trees that stay in a pot for years are especially vulnerable unless re-potted.

These steps will ensure success when re-potting into a larger container:

  • When moving plants to a larger container, (one size larger at each stage), re-pot in early spring as soon as they show signs of growth
  • Remove a little of the old compost, slide the plant out and tease out roots, cutting them if necessary
  • When it is no longer convenient to repot them every year into a bigger pot, they should be repotted in the same pot at least every other year. Replace one-third of existing compost and roots with fresh compost

In years when re-potting is not carried out, topdress by removing 5cm (2in) old compost from the top of the pot and replacing with fresh compost.

Summer care

Plants in containers need attention all year, but summer is the most critical period as plants can soon run short of water and nutrients.


  • Check for moisture daily from April to September (twice daily in hot weather)
  • Water thoroughly, filling the container to the rim and allowing it to drain, then filling it a second time to ensure that the whole of the compost is adequately moistened
  • If water is not draining out freely, check the drainage holes for blockage and assess compost structure – as the organic components decay, the compost becomes soggy, dense and lacking in air spaces
  • Lining or sealing terracotta pots with waterproof materials is unlikely to significantly reduce the need to water as most water is lost though plant leaves
  • Grouping pots for mutual shade will reduce heat stress on pots
  • Mulching pots will help reduce heating and suppress weeds, but as most water is lost through plant leaves careful watering will still be needed


  • From April to the end of August use a general-purpose proprietary liquid feed or, preferably, a high-nitrogen feed
  • Alternatively, add a controlled-release fertiliser at planting time
  • With soil-less composts, make sure fertiliser includes essential trace elements
  • After late summer feeding is usually suspended until mid-spring; however bedding plants and other short-lived annuals will still benefit from feeding until early autumn
  • Feed when the compost is moist

Winter care

In winter, the main danger is compost freezing, which may kill plants.

Frost protection

  • Protect pots with bubble plastic or bring them under temporary cover
  • In very wet periods move plants under temporary cover if the compost becomes sodden, until it has dried out a little. The ‘rain shadow’ of walls can be sufficient
  • In wet weather, raise pots up off the ground on ‘feet’ or similar to keep the bottom of the pot out of the water
  • Remove saucers in winter


  • Watering may still be necessary for conifers and other evergreens, especially if you have moved them under cover, so that they receive no rain. Check evergreens and conifers at least weekly and water if needed
  • Watering is seldom necessary for deciduous or other dormant plants


  • Feeding is not necessary during the winter months


Overwatering is the most common cause of loss of container plants; watering should aim to keep the compost moist, never soggy and avoid alternating dryness and saturation.

Plants grown in containers suffer from many of the same pests and diseases as when grown in beds and borders, such as aphids, algae, liverworts and moss and scale insects. Vine weevil and fungus gnats are particularly common pests of container-grown plants.

Overpotting is another common cause of problems.

Gardeners' calendar

Advice from the RHS

Find out what to do this month with our gardeners' calendar

Advice from the RHS

Did you find the advice you needed?

RHS members can get exclusive individual advice from the RHS Gardening Advice team.

Join the RHS now

Discuss this

for the site or to share your experiences on this topic and seek advice from our community of gardeners.

  • jenny wren 59

    By jenny wren 59 on 17/08/2014

    have just discovered that my acer palmatum has become waterlogged & has never happened before! i dont know how long it has been like it, the roots however go down below the pot into the ground & as it is a very large pot it is impossible to move it. What can i do as the water doesnt seem to be draining away & im scared it will die. It is approx 10 yrs old.

    This comment has been reported and is currently under moderation.

    0 replies

  • Heather1

    By Heather1 on 05/11/2014

    When I wrap my outside plants with bubble wrap, do I enclose the bottom of the pot or leave it exposed?

    This comment has been reported and is currently under moderation.

    1 replies

    View replies
  • carrot top

    By carrot top on 07/02/2015

    I have an alleyway full of mostly evergreens and trees in big troughs some have mulch some have not, my question is: should I fluff up the soil so that its not compacted as much? And should I add some fresh compost now to provide some protection from the frosts we've been having? I have plum trees, cherry, fig, malus john downie, golden hornet, that also need some pruning but im not sure where to start on 5ft trees! Thank you.

Get involved

We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.