Best Practices for Watering Plants


Summer is vacation season, and if you’re leaving home for more than a few days, you’ll probably need to ask someone to water your garden and containers. When I’m away, my instructions for which plants need to be watered and how much and how often to water them, is usually at least two pages long. Even with that, I can come home to plants that have been under- or over-watered.

Not that I’m surprised. Learning how to water plants is more difficult than it sounds. To get it right, you need to consider a lot of different things — like the type of plant, its size, the soil, the weather, sun exposure and time of year. When you’re watering plants, you need to be paying attention, not just doing a rote task. That may be asking too much of someone who is doing you a favor while you’re away, but it’s a good opportunity to review the best practices for watering plants:


1. Water Where the Roots Are
Focus the water at the soil level and keep applying it until the plant’s entire root ball is thoroughly soaked. Remember that the roots are probably the same width as the plant and may be a foot or two deep.

2. Check the Soil Before Watering
The best moisture meter is at the end of your hand. When the soil surface looks dry, probe down a few inches to see if the soil is dry several inches down. If so, it’s time to water. If not, wait a day.

3. Water Slowly
If the soil surface is dry, water may puddle or run off and not be absorbed. The solution is to start slowly and gradually build up to a thorough soak. Once the top few inches are moist, the water will be absorbed more easily.

4. Make Every Drop Count
Use a watering wand, drip irrigation or soaker hoses to direct water right to the root zone. Water early or late in the day so water will soak into the soil rather than evaporate. Shield plants from wind to reduce moisture loss.

5. Don’t Overwater
Plants need oxygen as much as they need water. For most plants, it’s best to let the soil surface dry out a bit between waterings. This is especially important with container plants. It’s always best to water deeply and less frequently.

6. Don’t Let Them Go Dry
In the heat of the day, plants sometimes wilt to conserve moisture, but they should perk up again when evening comes. If the soil get too dry, the fine, hair-like projections on the ends of the roots may be damaged. Though they can regrow, it saps energy that would otherwise be going to flower and fruit production.

7. Use Mulch to Conserve Moisture
Covering the soil with a thin layer of organic mulch such as compost, shredded bark and pine needles, to help reduce evaporation and minimize runoff. If the mulch is too thick, it can work against you by preventing moisture from reaching the roots.

To become a watering pro, it takes time and lots of in-the-garden experience. As the great American horticulturist Liberty Hyde Bailey wrote in 1917, “the watering of plants usually exhibits the skill, or the lack of it, of the gardener. It is a practice that cannot be well explained in print, although a few general statements may be made.”  

To learn more about caring for your garden, you might be interested in reading: How and Why to Fertilize Your Plants.