Indoor gardening: Houseplant grooming
From pruning to training, keep your houseplant lush
Regular deadheading, training and leaf cleaning do much to improve the looks of houseplants. Deadheading—the removal of dying or dead flowers—encourages some plants to produce more blooms, particularly African violets (Saintpaulia), streptocarpus and seed-raised pelargoniums.
When deadheading wax flowers (Hoya) and any other plants that produce permanent flower stalks, take care not to remove the stalks, as doing so will reduce future flowering.
After initial training, continue tying in new shoots of houseplants and replace any ties that have deteriorated or are restricting growth. Also, tuck in aerial roots on moisture-loving climbers such as swiss cheese plant (Monstera deliciosa) and epipremnum.
Grooming tasks during the growing season include pinch pruning young shoots—also referred to as stopping—on plants that are grown for their attractive foliage. This encourages a bushy shape by stimulating side shoots to develop and preventing the formation of flower buds.
On soft stems, just remove the growing tip with a finger and thumb; for tough woody stems, use a pair of sharp scissors or a pruning knife. Regular pinch pruning is particularly important for trailing plants, which can otherwise become long and leggy with leaves mainly towards the growing tip.
Household dust makes foliage look tired and dirty. Worse, if allowed to accumulate it can block the breathing pores in leaves and prevent maximum daylight from reaching the surface. Remove most of the dust while it is dry, using a soft paintbrush or shaving brush. This is the only way to clean hairy leaves.
Shiny foliage, however, can then be washed and polished. Wipe large leaves with a sponge or lint-free cloth. Proprietary wipes are also available. Be especially gentle with plants such as stag's horn fern (Platycerium), as the leaves have a waxy coat, which should not be removed.
The best way to remove dust from plants with numerous small leaves is to stand them outdoors in gentle rain or spray them with clean water. Do this early in the day so plants have time to dry off before nightfall.
Top tip: For an authentic shine and to avoid the unnatural appearance often given by leaf polishes, clean leaves (here of medinilla) with a little warmed milk. Use only a light touch when wiping each leaf.
Mature leggy plants can be much improved by pruning out weak or over-long stems. This minor pruning can be done at any time and promotes a burst of young growth from near the base of the plant.
More drastic pruning, when a large proportion of old growth is removed to encourage good shape and vigour, is best undertaken in spring, just as growth begins and before repotting, should this be necessary. Cut back hard all, or nearly all, the old stems, and prune out dead, damaged and straggly growth.
Then thin crowded and crossing stems, and shorten all remaining main stems by up to half, cutting just above a bud or a strong new shoot. Pruning tools should be very sharp and clean.
Woody stems should be cut with secateurs or long-handled pruners, according to the thickness of the stem, while dense bushy growth can be removed with pointed scissors, and soft shoots with a pruning knife or pinched out between finger and thumb.
- Untie climbers such as jasmine and passion flowers (Passiflora) before shortening older stems.
- Over-tall single-stemmed plants such as rubber plants (Ficus elastica) or dracaenas can be cut 1m (3ft) or more below their tips; new growth will appear after a few weeks.
- Philodendron and ivies (Hedera) can produce thin, almost leafless shoots in winter, and these need to be pruned back to their point of origin in spring.