Everyone thinks they know how to water a plant, when in reality, we all stand to learn. I was recently reminded of this fact when my daughters, both of whom are new to gardening, expressed to me that they “had no idea how important watering was” for plant growth. Like many people during the pandemic, they have had a bit more time to practice some new gardening skills and are learning by trial and error how to water their plants. But even longtime gardeners who know the importance of watering can use an occasional refresher on this essential gardening task. Here are a few tips for gardeners new and old to “water well.”
In summertime, our garden beds and containers rely on our knowledge and skill in keeping them supplied with water and nourishing fertilizers. Vegetables, perennials and annuals in garden beds benefit most when watered early in the morning. When temperatures are cool and the air contains some humidity, water is less likely to evaporate off of the soil surface before reaching plants’ roots. This also gives leaves time to dry off, which reduces the chance of fungal growth. The amount of water depends on the type and age of the plants. Generally, you want to give planting beds water for at least 30 minutes to ensure that it percolates to the root zones. Don’t be a “squirter” who spritzes your plants with the watering hose, thinking that you have sufficiently watered. And if it rains, don’t assume your plants are wet, either. They may have missed out on the rainfall due to overhanging foliage, so it’s always a good idea to check the soil moisture near their roots. Conversely, when sunny skies return, plants that are well watered may wilt. This doesn’t mean they need more water; the leaf cells are just adjusting to the bright light. They will return to a turgid state on their own, so resist the urge to overwater them.
If you have added young trees to your landscape, it is important to monitor them for two years as they establish their root systems. They need at least two inches of water, two times per week on their root zones. And you’ll want to avoid spraying the trunk of any newly planted trees by directing the water toward the planting hole.
Watering Plants in Containers
Plants in pots seem to flummox gardeners, but there are a few simple steps you can take to ensure success. First, the container must have holes for water to drain. This may sound basic, but it’s the most important part of watering, since the water applied to the surface must drain and fill the small spaces in the planting media. As it drains, water pulls air into and around the roots and pushes out excess fertilizer salts. Plant roots need nutrition, water and air to grow well, and the goal is to keep these three in balance. This is why, when starting new plants in pots or repotting a plant, it’s important not to oversize the container. You must pot a small plant into a small container until its roots seek out moisture and grow into that pot size, or else that balance of aeration and water is thrown off by an excess of waterlogged soil that roots cannot penetrate.
Some houseplants are very sensitive to increased salts in the soil, so you will want to water until you hear or see water draining out of the pot. If you have a grower’s pot sitting in a more decorative container that lacks a drainage hole, you will need to empty the collected water from the outer pot. With any containerized plants, you will want to water them at the soil line and avoid getting water onto leaves.
As you learn to water plants in pots, try these techniques to monitor their watering needs:
Pick up the pot to feel the weight. If the pot is overly dry and light weight, you will want to set it into a water filled saucer to let the media pull water up into the pot. If you water an excessively dry plant from the top, the water will run off the sides of the growing medium and not percolate through.
Test the soil moisture using the middle of your fingers between the first and second knuckles. This area of your hand is more sensitive to moisture than your fingertip. You can also stick a pencil into the soil to see if it comes out moist, much like testing a cake to see if it is fully baked. Soil moisture probes are also very reliable!
As with all things in gardening, patience is key. As you feel out your own situation, over time you will develop an intuitive sense of your plants’ watering needs. With these tips, hopefully you can expedite that process. “Water well” and enjoy your success!