Greenhouse, conservatory and houseplants


Move conservatory plants, such as Cymbidium, Ficus and Citrus outdoors during warm days but bring back inside if cold nights are expected.

Clean shiny-leaved plants (such as Anthurium, left) with a damp cloth and spiky plants with a soft brush.

Pot up houseplants showing signs of being rootbound or top dress large containers with fresh compost.

Cool conditions and regular watering will help keep potted indoor azaleas looking good for longer. Remember to water azaleas with rainwater collected in a rain butt, not with tap water.

In the greenhouse

Apply shade paint to the outside of the glass or use blinds on sunny days to prevent temperatures from soaring.

Open doors and vent on greenhouses to increase ventilation on warm, sunny days.

Damp down the floor of the greenhouse regularly on hot days, to increase humidity levels. This benefits plant growth and also reduces the risk of pest problems such as glasshouse red spider mite.

Don’t forget to give greenhouse plants more space as they put on new growth. This will help to prevent disease, and to contain early pest infestations.

Harden off your half-hardy bedding plants that were started off early under cover. By placing them outside for a short period only, at the warmest time of day, and then gradually increasing the length of time they are outside, you can avoid the ‘shock’ that they otherwise experience when moved outside suddenly and permanently.

Check plants at least every few days, to see if they need watering. Seedlings will need daily attention. Use rain, grey or recycled water wherever possible.

Continue to prick out and pot on new seedlings and cuttings.

Try growing on plug plants in your greenhouse. They are a relatively cheap source of large numbers of plants, and avoid the need for propagation facilities and time-consuming pricking out.

Hydrangeas and fuchsias can be propagated from softwood stem tip cuttings.

Pot on any Begonia, Gloxinia and Achimenes plants that you started off earlier in smaller pots, but which are now large enough to re-pot in the next size up.

Pruning and training

Train the new stems of passionflowers (left) and other glasshouse climbers over frames or on horizontal wires.

Remember to tie in the leading shoots of indoor crops such as tomatoes, peppers and aubergines as they grow. Stems are much less likely to break or grow in undesired directions if they're trained from early on.

Pest and disease watch

Regularly inspect plants, and also the structures of the greenhouse and conservatory, for glasshouse red spider mite, whitefly, thrips and other pests. Paying careful attention to the undersides of the leaves, and to each plant in turn, can spot early infestations that would otherwise be missed. Remove by hand or use biological controls, hang yellow sticky traps to help monitor numbers of flying pests.

Damp down the floor of the glasshouse regularly on hot days, to reduce the risk of glasshouse red spider mite.

Brush up fallen compost and debris, and pick off dead leaves from plants. This will help prevent pests and disease spreading.

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