Plants need a few things in order to thrive, primarily adequate light, nutrient-rich soil, and sufficient water. Water is one of the six essential nutrients for all living things. In plants, water is required for seed germination, nutrient transportation, photosynthesis, transpiration, and structural support.
Too much water can be just as harmful as too little. Overwatering plants can lead to root damage and rot, increased disease risk, yellowing and wilting, and stunted growth. Many of these symptoms are similar with plants that receive too little water. Underwatering plants can cause wilting and yellowing, crispy or dry leaves, leaf drop, slow growth, and poor performance. Finding the “Goldilocks” spot where we provide enough water, but not too much, is critical for plant health.
There are several factors that affect a plant’s water needs, including it’s species and variety, phase of production, and environmental conditions like the soil type and texture. In our part of the state, we tend to have heavy clay soils, which holds water and doesn’t drain well. In some ways, this is a good thing, because in times of drought, our soil tends to hold more water reserves for plants. It also holds on to nutrients and fertilizer better than other soil textures. However, during periods of heavy rain, our soil can become waterlogged, decreasing soil oxygen for roots and contributing to plant stress and disease.
Before you plant, consider testing your soil drainage. Dig a hole about a foot deep, fill it with water and let it drain, then fill it a second time. If that water doesn’t drain within 24 hours, you will most likely have problems with planting in that area. To improve drainage, consider adding and tilling in topsoil or organic matter.
Plant selection, location, and production phase also matter. Drought tolerant plants, such as a cast iron plant typically need less water than plants that prefer wet, swampy conditions like swamp sunflowers. It’s important to learn about the plants in your landscape in order to develop an effective watering strategy. Also, consider arranging your landscape so plants with similar water needs are grouped together – this can ensure you don’t over-water some and under-water others when irrigating.
Phase of production also matters, particularly for vegetables, fruits, and tree nuts like pecans. These plants have increased water needs when they are actively producing and filling out their crop, so you’ll want to accommodate this when you plan your irrigation schedule.
In general, most plants need around one inch of water per week, given in one sitting to ensure deep penetration of the water into the soil. If we get sufficient rainfall, you may not need to add supplemental irrigation at all. Irrigation should never be done on a specific schedule unless you are trying to establish new plantings or turf, instead, irrigate only when the soil is dry at a depth of 4-6”. If soil is dry and powdery at that depth, more water is needed. Always try to water first thing in the early morning, which reduces risk of wet foliage and disease development. Lastly, consider adding 2-3 inches of mulch around your plants to help conserve moisture.
Proper watering at the correct frequencies and amounts can help your plants grow and thrive. If you need help with a plant problem, disease, or pest, please contact us at uge3181@uga.edu or 706-359-3233.
