Like all life on earth, water is essential to the survival of the houseplant. Yet knowing when and how to water a plant can be a tricky proposition – don’t water it enough and the leaves will curl and turn brown, the flowers wilt and die; water it too much, and the soil will become waterlogged, its roots drowning and rotting beneath the surface.
Some people make watering the plants part of their weekly chores, schedules with the vacuuming and laundry. This is a mistake. Every plant has its own watering needs, and for this reason it is imperative that you get to know your houseplants individually. For example, succulents such as cacti very rarely need any watering – in fact, their soil should be nearly bone dry before any water is added to the pot. Flowering plants, however, require their soil to be damp at all times, which would obviously require the plant owner to pay more careful attention to the soil, even on a daily basis.
Determining the amount of water a plant needs depends on several factors. The first is the type of plant itself. As mentioned earlier, most succulents and cacti do not require much in the way of watering, as their fleshy leaves retain water for a great deal of time. Foliage plants often need to be watered more frequently than succulents, but less than flowering plants. For foliage plants, it is recommended to let the top layer of soil dry out before watering thoroughly. For many flowering plants, the soil should remain damp at all times. This can be tricky, because it is easy to over-water these plants in overzealousness. Your best bet is to water more frequently but in smaller amounts.
The environment is another important factor in the amount of water a plant requires. Plants left in an over-heated, dry room in winter will need more water than most plants during the resting season. An unusually hot summer will leave the plants thirstier than usual; a cool, damp spring might leave them requiring less. The type of pot plays a role as well – smaller pots (because there is less space for the root system to absorb water) will need more frequent watering than larger ones; and clay pots, because of their porousness, will require more watering than plastic, impermeable ones.
Finally, the season plays one of the biggest roles in the need for water. Spring and summer are the growing seasons – this is when plants will require the most water if they are going to remain healthy for another year. The winter is the resting period, and it is very important that the plant get this chance to rest so it can rejuvenate in the spring. It may be tempting to continue watering as you had before, especially if the plant seems to be growing new leaves during the winter, but it is better to cut back and allow the plant to recuperate. It’s crucial to not forget this during the winter months; too frequent watering can lead to waterlogging, leaf fall, root rot, and a host of other problems.
How can you tell when its time to water? You have two options. First, and most simply, you can gauge water level by both sight and touch; for example, with foliage plants, look at the soil itself. If it looks dry to you, stick your finger into the surface about a half-inch or so, just up to your nail. If your finger remains dry, it is time to water. If it is damp, you can wait a while. Another possibility is to buy a water meter at any garden center. These consist of metal probes which, when plunged into the soil, report a saturation level on its display. Most of these meters come with guides listing hundreds of plants and what the proper saturation level is for them.
There are two popular watering methods. The first is the traditional technique most everybody associates with gardening – the watering can. When using a watering can, make sure to angle the spout beneath the leaves and flowers, especially if the sun is shining on the plant. Water can intensify the effect of sunlight, and splashed leaves in direct sun will be scorched. If you can, try and water in the morning time, before a full day of sunshine. It’s okay if some water comes through the drainage hole at the bottom of the pot – but if the water runs straight through, you may have a problem with the soil pulling away from the sides of the pot. In this case, you may need to repot or add more soil. In the meanwhile, you can use the other method of watering, which is known as immersion. This involves plunging the entire pot into a basin large enough to hold the entire plant with its foliage above the water. Make sure the water does not rise above the lip of the pot. Let the plant sit in the basin; it will draw water up through the drainage holes and its root system. When the surface of the soil looks damp, the plant is sufficiently watered.
