Conservatory Plants and Houseplant Care

Care of Conservatory Plants and Houseplants

Please be aware that temperatures in an unheated Greenhouse or Conservatory can drop below freezing in winter. Do not rely on the protection of a cold greenhouse alone to overwinter plants that need to be kept above freezing.

It is very important to not to over water plants. Before you water always check the compost with your finger. If the surface is dry then water but if it is moist leave and check again in a couple of days.

Plants take up water through the roots and lose moisture through the leaves (a process called transpiration).  If you water too much the leaves cannot transpire quick enough.  Roots need oxygen and if the compost is kept saturated they suffocate. This leads to root rot and ultimately death of the plant. If the compost is damp this means the plant still moisture available and does not need any more for now.

Plants with small leaves have evolved to cope with dry conditions by reducing the surface area of their leaves. Succulents have fleshy leaves which store water. Particular care needs to be taken not to over water these. The advantage is they can be easy plants to look after and a bit more tolerant of neglect.

It is not possible to say how often plants will need watering it really depends on where they are growing, how much sun they receive and the time of year.  It’s really a case of trial and error, checking plants regularly and watering them only when the compost is almost dry. Plants on a sunny window sill or warm conservatory should ideally be watered in the morning before they receive too much sun to avoid them getting stressed.

You can use tap water to water most Conservatory and House Plants but if possible try to use rainwater as this contains natural essential nutrients that help plants grow well. Some plants like Orchids, Bromeliads and acid-loving plants should only be watered with rain water.

Potting On
IMPORTANT: Potting on should only be done when plants are in active growth. We suggest letting your plants acclimatise for a couple of weeks after you receive them before moving them into  larger pots – this gives them time to adjust  to their new surroundings in terms of light, heat and humidity.  The best time for most plants is in the spring when new shoots are emerging. The size of pot should be increased gradually when potting on prevent the excess compost from becoming stale before the roots have had chance to penetrate it. This also helps avoid the problem of over wetting.
Conservatory plants are best NOT potted on after July/early August – this gives the roots time to establish in the new compost before the winter. If a plant dies it is usually as a result of late potting and/or being put in too large a pot. They seldom die due to being slightly or moderately pot-bound in the winter months. 

It is important to provide good quality compost for plants if they are to perform well.  We recommend using a houseplant compost or John Innes No. 2 or 3 for most plants.  Succulents and Cacti should be grown in Cacti compost or John Innes No. 1 with plenty of horticultural or washed grit added for drainage. Acid-loving Houseplants, Bromeliads and Orchids should be grown in the appropriate specialised composts which are available at most garden centres.

Most plants grown indoors really benefit from being misted daily with a hand-held spray. If this is not convenient then try standing them together on a tray with a layer of gravel and water filled to just below the top of the gravel to keep the bottom of the pots clear of the water.

It is important not to over feed and to only feed plants when they are in active growth. Never feed dormant plants. Over feeding can cause excess growth and growth distortion. When potting up incorporate some slow release fertiliser granules (available from most garden centres) into the compost to gently feed plants over a period of time. For plants which are not potted on, top dress by removing the top layer of compost every spring and sprinkle a small pinch of slow release granules and cover with fresh compost.   Always follow the manufacturer’s instructions and only apply fertilisers when plants are in active growth.  Generally speaking Cacti and Succulents should not be fed at all. Flowering plants will benefit from a liquid feed for House Plants during the growing season. Leafy plants or those which don’t flower much should be fed with a balance liquid fertiliser such as liquid Growmore.

It is important to ensure plants are situated where they will get the level of sunlight they require. Shade-loving plants like Aspidistras and Ferns should be sited where the will be out of the sun during the middle of the day. Sun loving plants should be placed where they will receive direct sunlight for at least half of the day however many appreciate being shaded from the hot midday sun. If they are showing signs of stress consider moving them to another position. Houseplants should not be placed directly above a radiator when the heating is on. The excessive heat will stress them and cause the compost to dry out. If you have Conservatory which is South facing and gets very hot in summer you will need to provide some shade for plants in the form of conservatory blinds or shade netting. Remember if you can’t bear the heat, neither can the plants!

Good ventilation is very important as it reduces the stress on plants in hot weather and helps to prevent pests and diseases. Ideally there should be ventilation low down and high up in a Conservatory to allow the hot air to escape and cool air to be drawn in from below. If it is not practical to achieve this consider moving plants outside for the summer especially if you are not at home much during the day and don’t want to leave windows open.

Support for Climbers
Climbers will need the support of a structure such as an obelisk to grow up. Large climbers will need wires positioned along a wall and or in the roof for them to grow along.

Unfortunately the problem with growing plants in an enclosed environment is they can sometimes become susceptible to pests which like the warm, dry atmosphere and lack of good air circulation. Looking after them and preventing stress along with good hygiene is the best way to keep them healthy. Make sure you leave space between plants to allow air to circulate around the leaves. Keep them sufficiently watered and move them away from hot positions if they appear stressed. Remove any dead growth which may harbour pests or diseases.  Some common Pests;






Sticky leaves. Distorted leaves. Tiny flying white, green or black insects on the underside of the leaves or flower buds.

Plants can be made susceptible if they are stressed by over/ under watering or over feeding.

Spray with soft soap or other organic pest spray. Consider moving plants outside for a time if weather is mild.

Mealy Bug

Sticky white deposits on undersides of the leaves. Small, oval white bugs may be evident. Plant has stunted growth/ general lack of vigour.

A warm, dry atmosphere and lack of good air circulation.

Spray with soft soap. Increase humidity. Remove infected growth/ dead leaves and thoroughly clean pots/ trays around window frames to remove any eggs.

Red Spider Mite

Very fine webbing on the leaves. Leaves have yellow speckles and have a dull appearance.

A warm, dry atmosphere and lack of good air circulation. Plants have become stressed.

Remove affect leaves, increase humidity and Apply Soft Soap or other organic pest control. Consider moving plants outside for a time if weather is mild.

Scale Insect

Very tiny orange, scaly blobs on stems or the underside of the leaves

A warm, dry atmosphere and lack of good air circulation. Plants have become stressed.

Scrape off by hand or apply soft soap/ other organic pest control. Re-application will be needed to remove all of them. Increase humidity

Woolly Aphid

Fluffy, cotton-wool like deposits on the stems/ leaf joints.

As above



Spray with soft soap or other organic pest spray.