Watering Myths – The big questions
It has rained a bit the last few days, so the pressure to water in the garden has been lifted, at least for a while. However, with the temperatures rising and the winds continuing to blow, the need to water will again be present, and we all need to understand some basic do’s and don’ts about watering in the garden and the landscape as well.
There are some “truths” that we need to dispel quickly.
Truth 1 – “Watering should be done regularly and on a schedule.”
I suspect this one came from the irrigation industry. The easiest way to water “regularly and on a schedule” is with an automatic irrigation system. Apparently, there is a lot of buy-in on this one. I drive around town when it does rain and see sprinkler systems busily delivering water even as it pours down rain — what a waste of precious resources.
The real truth here is that landscape and garden water needs vary. Water should only be applied when necessary. Plant’s water demands also vary, and that can affect how much and when you water individual parts of your landscape. Even turf grasses can suffer from too much water. The biggest problem on turfgrass with frequent quick, shallow watering is the underdevelopment of root growth. Shallow, poor root growth leads to weak plants and opens them to disease and pests.
Know your plants and understand their water needs. Water only when necessary and water slowly allowing the water to infiltrate deeply into the soil. The goal is to have an even distribution of water throughout the root zone. Getting an even distribution in the root zone depends a lot on how well your soil infiltrates and how well you mulch to maintain that moisture.
Truth 2 – “Never water your vegetable and ornamental plants with a sprinkler because it can cause disease and burn the leaves.”
Think about this. How does nature deliver water to plants? It rains. Most sprinklers are designed to mimic rain. Now, watering with most sprinklers is less efficient than using slow flooding or drip systems. Some of the water will evaporate. If it is windy, it is hard to control where the water goes.
However, that being said, you don’t need to worry about scorching the leaves because the water droplets act like small lenses and magnify the sun’s energy. Total myth. In many ways, watering with a sprinkler occasionally actually helps by washing away accumulated dust and other debris from the leaves. A good sprinkle will also go a long way to removing spider mites and aphids from plants.
Truth 3 – “When your plant’s wilt, it is time to water.”
Plants wilt for any number of reasons. Yes, lack of water can be one. Too much water can be another. More often than not, that late afternoon droop you see in your vegetable plants is a normal response. As days get warmer, often the plant simply can’t replace the water it is losing through transpiration. Afternoon wilting can be due to insufficient root development, disease, pest damage, or poor soil health. Even healthy plants with good root development and in good soil will exhibit a bit of leaf wilt on the hottest of days. A light sprinkle over the top will help them perk up. As long as there is sufficient moisture in the soil root zone, the plant will recover as temperatures drop.
The Real Truths
The number one truth is that unless you check the soil, there is no way to know if you need to water or not. That can be done in several ways. If you are a tech person, there are soil moisture meters on the market that can help you judge the moisture content of the soil. My biggest problem with them is that the probes are usually short and only measure available moisture in the top two or three inches of the soil. There can be more than adequate moisture in the rest of the root zone, and adding additional water can cause problems.
Most people don’t realize that the drying of the soil is almost as important as the water. As the moisture evaporates from the upper layers of the soil, the open spaces between the soil aggregates aerate. Fresh air is pulled down into the soil, bringing fresh oxygen and nitrogen into those spaces. These spaces are where the majority of the soil organisms live, and this oxygenation is vital to good soil biome health.
Using a Soil Probe
The best way I have found to test soil moisture is to use a soil probe. My soil probe is made from the shaft of an old golf club. If you prefer, they are available from most garden supply shops for $15 to $20. Using a probe takes a bit of trial and error, but it is a skill that is easily developed. Push the probe into the soil. In time you will learn to tell by feel the condition of your soil. If the soil is too wet, the probe will make a sucking sound as it comes out of the ground. If the soil is too dry, the probe will be hard to insert. You will eventually be able to judge the depth of your moisture zone by the way the probe reacts as it goes deeper into the soil.
The picture is my soil probe. I made it from the fiberglass shaft of an old golf club. I like the fiberglass shafts because they are light and if I accidentally probe into an underground electrical line, I am far less likely to have a regrettable mistake.
You can see how deep I can easily push the probe into one of our raised beds. It actually takes very little effort to get the probe this deep, an indication that the soil is in good condition and that there is moisture present. When I remove the probe, the shaft comes out clean with just a hint of moist soil attached.
The Garden Journal
Your garden journal will become an invaluable tool, as well. Plants need different levels of moisture and knowing your plants can help you judge when and how much to water the varied plants in your garden — keeping notes of when and how much you water is important as well. It helps avoid accidental overwatering.
My last bit of advice is to mulch. Wood chip mulch is best. Avoid pine bark mulch, cypress mulch, and the manmade mulches like ground-up tires. Wood chip mulch protects the soil. It keeps it cooler in the summer and warmer in the winter, helping the soil biome survive extremes. It helps retain moisture in the soil by inhibiting evaporation. As it decomposes, it is adding fresh compost to the soil, continuing the process of feeding and building a healthy soil biome.
So, my advice? Turn off your automatic sprinklers and start paying attention to your landscape. Water only when necessary. Begin a systematic organic soil maintenance program to increase your soil health and the infiltration rate. Water slowly allowing the moisture to spread evenly down through the root zone. Check your soil regularly and water only when your plants require it.
Links and Resources
For more information about organic gardening, lifestyles, and living, visit our website at West Texas Organic Gardening.
If you found the information here helpful, you might also find these articles on our website of interest.
If you have more specific questions or problems, you can contact us using the contact form on our website. You can also post your question to our community forum at this page; West Texas Organic Gardening Community Forum.
We have a Facebook page and love your comments, questions, or input. You can find us on Facebook using this tag. @westtexasorganicgardening