Caring for your houseplants properly

Providing the proper treatment and correct cultural conditions for a plant will take you three parts of the way along the road to successful growing. But all the proper treatment and conditions ever invented will be of no avail if the plant purchased is sub-standard. If a plant leaving a greenhouse, where it has had almost ideal growing conditions, is of poor quality, there is not much hope of it doing well in the home where conditions are likely to be much less agreeable. So look for healthy plants to buy and the end result will be very much more satisfactory.

Plants are very much like people in their requirements; they are much more likely to respond favourably to conditions and treatment that offer moderation rather than excess. Too much of almost everything will be detrimental to both flowering and foliage plants – too much water, too much heat, too much fertilizer, too much attention. By the same token almost all plants will suffer if there is too little water, fertilizers and such like. Moderation is the key word.

If the plant you purchase does not have a tag attached giving some advice concerning its particular needs, then refer to a book on the subject and follow the instructions given. An even amount of warmth throughout the 24 hours of the day is important, and if somewhere in the region of 13°C/55°F can be maintained it will suit the vast majority of foliage plants. Ivies, though, are an exception as they prefer cooler conditions in the region of 10°C/50°F. If grown in hot, dry rooms they quickly become dry and shrivelled.

Given reasonable warmth, the next most important need is for good light. Daylight is preferable, although many plants will do perfectly well if illuminated entirely by artificial light that is suitable for plant growth. Or use a mixture of artificial and natural daylight. Where the recommendation is that plants should be grown in the shade this does not mean that they ought to be relegated to the darkest corner of the room, although there are those plants, such as marantas and the aspidistra, that seem to do better in areas where the light is more restricted. On the whole, however, although many plants object to strong, direct sunlight, the majority will do little more than survive in poorly lit locations.

Some plants will do fine in full sunlight all the time and the two that really thrive in such positions are mother-in-law’s tongue (Sansevieria trifasciata ‘Laurentii’) and the highly coloured crotons. The latter will quickly lose their brilliant colouring if adequate light and sun are not available. During the winter months, plants on the windowsill may suffer as a result of cold draughts, and it is advisable to move any from windows at night if these are not double-glazed. But plants should not come to any harm from the sun which is much less intense at that time. During the summer months, however, it may be necessary to remove plants from south-facing windows where they may become scorched, or where leaves will almost surely take on a harder appearance. Filtered sunlight, such as through net curtains or Venetian blinds, will be adequate protection. Also, to prevent foliage becoming scorched by the sun, it is important when watering to ensure that the leaves of the plants do not become splashed.

Watering is in all probability the most difficult operation for the inexperienced gardener to understand. More houseplants are killed by overwatering than by any other cause and most plants either get far too much or far too little. Excess in either direction will result in damage to the roots of the plant. Such damage will later be reflected when leaves lose their colour and take on a generally sick appearance.

When watering plants it is important that the entire rootball, this is all the soil and the roots, is thoroughly saturated. The best way of ascertaining this is to fill the space between the rim of the pot and the surface each time the plant is watered. Excess water should be seen to run through the hole in the bottom of the pot, and if water is not seen to do so reasonably soon after watering, then a further watering should be given. (Another point to watch when watering: if the water drains through very quickly, the plant could be pot-bound and require re-potting.) Plants growing in a group arrangement in a large container cannot be tested for sufficient watering by this method. You will have to use the old-fashioned ‘finger into the soil’ test. The soil should be allowed to dry out a little between waterings, but it should not be allowed to dry excessively unless the plant is in a dormant period, not requiring any water. Some plants need more thorough soaking and should have the plant pot plunged in a bucket of water until all the air in the pot has escaped. Although other plants may be watered by this method it is more essential for moisture-loving subjects like the indoor Azalea indica and the hydrangea. Allowing the hydrangea to dry out during its growing season, or the azalea to at any time, will result in general deterioration.

To some extent capillary watering containers take the hit-and-miss aspect out of watering as the fitted water level indicator clearly shows how much water is in the container reservoir, and how much is required. The important need with such containers, however, is to ensure that they dry out completely between each watering and to allow the reservoir to remain dry for four or five days before refilling. This will permit the soil to become aerated, which is essential for the plants to develop a healthy root system.

If a plant does become waterlogged, take it out of its pot (the entire rootball) and leave for a day so the air can dry the soil. After this you can return it to its pot – and water more carefully! It also helps to stir the crust on the top of the soil in the pot occasionally.

Growing plants in water, entirely without soil, has been experimented with for many, many years, but never seemed to present a challenge to plants grown more conventionally in soil. In recent years, however, a marked change has occurred, so that hydro-culture is now very much on the increase. Not all plants, such as the ivies, are suited to hydroculture and there are many experiments being carried out to see which plants are suited to conversion from soil-growing to water-growing. Fortunately the vast aeroid family, many of which are used for indoor decoration, seems to be especially adaptable to this method of growing.

Plants of almost any size can be converted. The procedure is first to wash off every vestige of soil from around the roots, then to place the plant roots in pots with open slotted sides. The area around the exposed roots is filled with clay granules, which absorb water and help to keep the plant upright. The pots are partially submerged in water and after about two months, the majority of plants produce sufficient water roots for them to be considered fully converted. They can then be planted up in more decorative containers and introduced to the living room.

In the decorative container there is a water level indicator to show when refilling is needed, and a tube through which fresh supplies of water can be poured. The same tube performs a dual purpose in that it is also used for syphoning water from the container when a complete change of water is necessary. This usually occurs every six months, but it may extend to 12 in some cases. A slow-release fertilizer is used for feeding hydroculture plants and, depending on the manufacturer’s recommendations, need only be given every six or twelve months. Although plants grown by this method are more expensive than plants that are grown more conventionally in soil, there is no doubt that the general cleanliness and efficiency, not to say the improved standard of plant growth, has much to recommend it.

During the summer months many of the easier plants will benefit from being placed in a sheltered place out of doors where they will not be exposed to too much direct sunlight. The Calomondin orange (Citrus mitis) will, however, be very much improved by spending the summer months in as much sunlight as there is available provided the soil is never allowed to dry out.

Sorry, comments are closed for this post.