Which plants are best for an unheated conservatory?
Elaine Brown, South Wales
AMATTHEW
P SAYS I find plants of borderline hardiness are best for unheated conservatories, like yours. The physical structure protects them from frost, they can cope with cool temperatures and escape excessive wet, which can often contribute to winter deaths.
If you have space, try the lovely New Zealand tree fern Dicksonia squarrosa, which is more compact than the outdoor species we often see, and a flowering climber such as Hardenbergia violacea, with its purple flowers, or Jasminum polyanthum for its incredible scent. Also add a bowl or two of succulent Echeveria elegans, which is happy on windowsills.
Also try a Chile lantern tree, Crinodendron hookerianum, which has red flowers, or one of its cultivars, such as ‘Ada Hoffmann’, which has pink flowers. While this shrub grows well outside in some parts of the UK, it dislikes wind, exposure and cold temperatures, preferring acid soil, so the protection of your conservatory should help it to thrive.
Keep houseplants such as peace lilies away from any draughts
AMATT
B SAYS You say your conservatory is very cold in winter but hot in summer, so first install some sort of winter heating and improve the ventilation (but do not create draughts) to reduce temperatures in summer, so you can grow a wider range of plants that enjoy shade or low light as your conservatory faces north.
Try the Boston fern ( Nephrolepis exaltata ‘Bostoniensis’) for its dense clump of mid-green fronds, and the peace lily ( Spathiphyllum wallisii), with its white blooms and dark-green leaves. Aglaonema ‘Silver Queen’ has silvery-grey leaves with dark-green markings, while foliage begonias come in many patterns and colours.
The parlour palm ( Chamaedorea elegans) and Kentia palm ( Howea forsteriana) enjoy humidity, so group them together or stand them on a tray of damp pebbles.