Watering to Beat the Summer Heat

One inch of rain per week is generally adequate for plants that are located in the ground. If you don't already have one, a rain gauge is a great tool to help you determine if last night's rain shower was enough or if you need to supplement. Rainfall amounts can vary widely in a geographic area—one town might get 3", another none, so the gauge helps you keep track of what happened in your own garden.

Vegetables and herbs planted in containers will need more water on a regular basis, particularly pots that are smaller than 10" in diameter. Most edibles also need sun, which means they need more water. Raised beds are much like large containers and if yours are less than 18" deep, water as you would a stand-alone, smaller container.

Especially with containers, try to water around the same time each day. If you water in the morning one day, then not until the evening the next day, your plants will endure two full days of sun and heat with only one watering.

Before you water, put your finger into the soil up to your first knuckle to determine how moist the soil is. Soil may appear damp or wet when it is not. If your container does not have a drainage hole in the bottom, make one or use another container. Most plants cannot survive with their roots sitting in water.

Guide the water as close as possible to the ground so most of the water sinks in and is available to the roots. Water on plant leaves evaporates and can cause burn on the leaves when the sun hits the water droplets. Directing water slightly above the soil between plants minimizes the amount of water on the foliage. This is a good method if your plants are spaced close together. If you are using a hose, a long-handled wand with a shut-off valve allows you to put the water where you want it and control the flow.

How do you know how much water to give your plants? When you are watering with a hose, it can be challenging to know how much water you are delivering. One way to gauge this is to run your hose into a bucket or watering can and count how many seconds it takes to get to the desired amount of water. If you count that same number of seconds as you hold the hose at individual plants, your watering will be more consistent.

During periods when there is no rain, monitor perennials, younger trees, and shrubs for signs of stress. Water slowly to allow moisture to go deeper into the ground.

Vegetable plants may need more water at some stages in their development, for example, when they are flowering, or seeds are growing larger.

Look for multiple sources of water. If you run your shower or bathwater until it gets warm, you can capture that water in buckets and use it on your vegetables. Some dehumidifiers have removable reservoirs that would allow you to use that collected water. Water from a children's pool can be used on plants. Finally, you can capture the water you use to rinse vegetables and fruit when you are preparing them for eating. Water with detergents or soaps should not be used on your plants. Softened water contains salt, and buildup could be a concern if you are using a container that gets no rainwater in addition to the water you supply.

Rain barrels are another great water source. I prefer the style that I can submerge a watering can into. Spigots at ground level with hoses attached can make it difficult to dispense the water since you are relying on gravity and water pressure to push the water out. If you plan to use a recycled container, be sure you know what was stored in the container or barrel so no harmful residue is absorbed into your collected water.

Slowing down the delivery of water gives the plant time to absorb the moisture. Plastic jugs and buckets with a hole drilled in the side will provide slow, deep watering at the base of the plant. As I mentioned earlier, a shut-off valve is also key for reducing water pressure from your hose.

Mulch can help slow down the evaporation of water from the soil. In addition to bark and wood mulch that is commercially available, dried leaves, straw, cardboard, or untreated grass clippings are options. Pull weeds that will compete for water and nutrition.

Hold fertilizer as some contain salts and can dry out the plant more. Many require moisture to sink into the soil.

If you find a plant that is dehydrated, here are some tips for rescue watering. If it's possible to move the plant out of the sun, first do that. Then give the plant a small amount of water. If you've run water over a hard, dry sponge, you know that it won't absorb water until the surface gets wet. It's the same with soil. If your container is small, you can put water in a tray or saucer and allow the plant to absorb water from the roots.

You have worked so hard to get your garden established; stick with a consistent watering schedule so you can enjoy the harvest!