The Basics of Watering Indoor Plants, by Jim Hole

Watering Gadgets

Many homes have great vertical spaces that are ideal for plants. The trouble is that while high ledges and tops of bookshelves are perfect spots for growing plants, they can also create inconvenient watering situations. Fortunately, there are many gadgets designed to make watering a little easier.

My best advice is to keep it simple.
A lightweight stepladder and a long-necked watering can is all you really need. Just be sure to choose a watering can you can comfortably handle. A plastic watering can might not weigh much when it’s empty, but fill it with water, hold it away from your body and watch just how quickly your arm starts shaking.

Hold the Fluoride…and the Chlorine, Please

Plants are not as enamoured of fluoride as we are. In fact, the fluoride in our tap water can be quite a problem for dracaenas, palms and ti-plants. Spider plants (especially variegated ones) are extremely sensitive to fluoride, so watch for signs of damage such as browning of foliage tips. If you want to avoid complications related to fluoride, water with distilled water or rainwater when possible.

If soils have adequate lime and a proper pH level, fluoride in the water will be tightly bound in the soil and not be drawn up by the plant roots.

Chlorine is another nutrient that can be hard on plants. If you grow chlorine-sensitive plants, like African violets, fill your watering can in the evening and let it stand overnight. This will allow the chlorine to evaporate and will also bring the water to room temperature.

There are many tools and gadgets on the market designed to measure soil moisture, yet very few are as reliable or as ‘handy’ as the 10 you
already have. There’s no secret method to checking whether a plant needs water. Just walk over and stick your finger in the potting soil, scratching down 2–3 cm into the soil. Moist soil should feel about as wet as a damp sponge. In fact, the soil should feel a little spongy, too. Even when the top layer of soil looks dry, there may still be plenty of moisture just beneath the surface.

How much water your plant needs and how often your plant needs it depend on the following factors:

  • Type of plant
  • Size of plant
  • Size and type of container
  • Soil composition
  • Humidity of the growing environment
  • Season
  • Location of the plant in the room
  • Average room temperature

Know your plant’s preferences and water accordingly. Don’t forget that although most plants will forgive you if you miss a watering here or there, some plants aren’t as tolerant. Boston ferns, for example, hate dry soil. On the flip side, cacti hate being too wet.

Watering Methods

Most plants get watered from the top, but that says more about people’s preferences than it does about plants. Most plants don’t care whether they are watered from the top or from the bottom as long as they are watered regularly and sufficiently. A general way to gauge whether you’ve given your plant enough to drink is to check for water running through the drainage holes at the bottom of the container. This runoff is particularly important because it flushes excess salts from the soil. Just be sure to drain any water that remains sitting in the base of the saucer.

Watering from the top

• Consider grouping plants together in the bathtub and giving them a gentle watering and shower. After you’ve watered, let your plants stay in the tub for a few hours. This will allow them to drain properly and keep you from tracking water across your house.

• Don’t water from high above your plant. Place the spout of your watering can close to the lip of the container and water from a different side each time. Watering from the same spot each time will wash away sections of topsoil and leave behind craters.

Watering from the bottom

Some plants, like African violets, prefer to wick water through the drainage holes in the bottoms of their pots, essentially drawing up water until the surface soil is moist. This method is particularly beneficial to fuzzy-leaved plants that tend to blemish when they come in contact with water.

-Jim