Correctly watered and fed, and kept in an environment with the right amount of heat, light and, your house plants will be handsome, healthy and long lived.
The difference between a house plant that glows with health and one that struggles to survive or even dies is often simply a matter of how youand water it. Watering and routines are seasonal; an increase or decrease in one often means a matching adjustment in the other. The golden rule is: if in doubt, use restraint. More house plants are killed by overwatering than anything else, and too much food is more harmful than too little.
The information here is for guidance – always keep the care labels when you buy new plants, as some have very specific needs.
How often you water varies according to plant,, , season and surroundings. Plant Only a few plants, such as the umbrella plant ( al-terniflorus), need continually wet compost. Generally, thin- or large-leaved plants and quick-growing plants need frequent . , succulents and plants with thick, fleshy or waxy , grey-leaved plants and slow growers need less.
Compost Plants in peattype compost need more frequentthan ones in loam-based compost. Container Plants in small or unglazed clay need more frequent watering than those in large plastic pots. A pot filled with needs generous watering. Season Growing and need watering weekly, twice weekly or even daily. Dormant plants can go for a week, a fortnight or, with , up to a month without water. Most plants grow in spring and summer; some (such as cyclamen, and ) grow in winter. Surroundings Plants in hot (especially centrally heated) dry conditions need more frequent watering than those in cool humid ones.
When to water
Moisture meters and tabs measure the exact water content of compost, but you can usually tell all you need to know by a quick look, or by feeling the compost. Plants in flower Keep the compost continually moist, but not soaking; water when it starts to look pale, powdery and dry. Foliage plants (especially vigorous climbers and plants with extensive roots and large leaves) In the growing season, water often enough to keep the compost con-tinually moist. When dormant, let the top 1cm dry out between watering.
Cacti and succulents When growing, let the top 1cm (%in) of compost dry out between watering; when dormant, let it dry out almost completely – water only if the plant starts to shrivel.
Feed growing and flowering plants regularly. Dormant plants,and newly rooted need little or no food. Repotted or newly bought plants have enough food for about eight weeks.
Whichever type ofyou use, follow the manufacturer’s instructions. Don’t feed too often, or give too strong a solution – rather than doing good, you are likely to damage the plant’s roots. Water before you feed – never add fertilizer to a dry compost. And never feed plants when they are dormant.
Only apply fertilizer to healthy plants: if a plant is ailing, do not assume it is malnourished. It’s far likelier to be incorrect watering, or a pest or disease – treat the problem before.
General, all-purpose or balanced feeds are fine for most plants. You can use potash-rich fertilizers, such as tomato fertilizer, to boost flowering, and nitrogen-rich fertilizers to promote leafy growth. There are special fertilizers for African violets,, , citrus trees, and lime-haters; and seasonal fertilizers for, say, a quick spring boost. Liquid fertilizers are available as a concentrated liquid or soluble powder. Diluted in water, they are easy to use and can be varied according to the plant’s need. Insoluble quick-acting feeds may be in granule or crystal form and are sprinkled on the com- post surface. They take longer to reach the roots than liquid feeds. Slow-release granules provide nutrients for up to four months. Add to compost when . Slow-release tablets and spikes pushed in the compost are easy to use, but they encourage uneven growth, and the amount of fertilizer released can’t be varied. Liquid foliar feeds, applied with a spray gun or impregnated sponge, give plants an instant boost, but are not suitable for long-term use.
Temperature needs are seasonal and reflect a plant’s growth cycle-usually active growth during spring and summer, dormancy in autumn and winter. Provide warmth for growing and flowering plants, cooler temperatures for dormant ones. Plants that lose their leaves when dormant need quite cool temperatures.
House plants are more liable to suffer from too much heat than too little – particularly in houses with central heating in winter. If in doubt, move the plant to a cooler spot. Always keep plants well away from direct sources of heat such as radiators, and provide draught-free ventilation.
Try to avoid wildly fluctuating temperatures, though a drop in night temperatures is often beneficial, especially in winter. It’s never a good idea to move plants between rooms of very different temperatures.
Plants left on windowsills at night in cold weather can occasionally suffer from frost damage, especially if the plant is behind closed curtains that prevent any heat from reaching it.
Provide cool but frost-free tem-peratures for winter-flowering hardy or nearly hardy plants such as azaleas, polyanthus, forcedand daffodils, to prevent premature withering of the blooms.
House plants need more light when in bud or flowering than when resting, so move them closer to a window if necessary – but take care they’re not in a draught.
Provide lots of light for coloured leaved and variegated plants, though prolonged exposure to direct sunlight scorches or bleaches some white or yellow leaves.
Display cacti, succulents such as aloes and most plants with furry, grey or waxy leaves in plenty of direct sunlight all year round.
The thinner the, the more you must protect the plant from direct sunlight. The delicate leafy fronds of maidenhair fern, for example, shrivel up when exposed to direct sunlight for long periods.
In winter, when light levels are low, move light tolerant house plants closer to a window. In summer, only cacti and some succulents can stand the intense light on a windowsill that gets full sun-light. Move other plants back or shield them with netting or blinds.
To prevent lopsided growth towards the light, give plants near a source of light such as a window a quarter turn every few days.
House plants benefit from being put outdoors in summer, in a sunny or shaded spot as appropriate. Shrubby flowering plants such asbenefit from sunlight ripening the wood, which encourages flowering.