CHARLESTON, W.Va. -- It seems that summer weather is either feast or famine when it comes to rainfall. Sometimes, storms dump large amounts of water on the West Virginia hills, or summer heat and drought scorch the earth. Both the overabundance and undersupply of water can have detrimental effects on the garden and landscape. The effects, though, can be mitigated with some good, water-wise gardening practices. Weathering storms While plants thrive with ample water, too much of a good thing can be bad. Puddles or pools of water in your garden or landscape is a sign of poor soil drainage, which can lead to plant health issues, including root rot and killing of root hairs. Root rots typically are fungal diseases that occur in an abundance of water. The roots die away, leaving the plant above to wither and perish. Water also displaces air in the soil, meaning that roots can suffer a lack of oxygen (yes, roots have to breathe) and result in death of root hairs or the total root. Without root hairs, plants will have a tough time taking up water and nutrients in the future and will fail to thrive. Excess water can cause other issues. Walking in plowed fields or gardens, landscape beds or even on the lawn when the soil is wet can compact the soil. Packing of soil makes it difficult for roots to grow and water to penetrate and run through the soil. Compacted soil can be a major issue for gardens. Working in the garden or landscape during wet times also can lead to the spread of diseases. Most of the fungal and bacterial diseases in the garden are spread by water, such as wind-splashed rain coming up from the soil onto the plant. Simply walking through the garden when leaves are wet can spread diseases quickly among many plants. Here are tips to reduce the effects of excess water in the garden:
Incorporate organic matter in heavy soils to improve drainage. Do not add sand to clay soils, as this is done every day at the concrete mixing plant.
Use unplowed walkways between rows or garden beds to limit compaction.
Install basic drainage such as diversion ditches to avoid heavy pooling of water.
Stay out of the garden and landscape when the soil is wet.
Avoid eating leafy produce that has been covered with floodwater. Take caution with other forms of produce.
Dealing with dryness
On the flipside of too much water is the dry scorch of heat and drought. Midsummer usually means long periods without adequate water for gardens and landscapes. Plant growth slows, leaves wither and gardens (and gardeners) languish in the heat. It is important to have a plan to deal with the summer dehydration to keep your gardens looking healthy.
A typical garden requires at least the equivalent of one inch of rainfall per week to keep plants performing at their top potential. That means each square foot of garden or plant space requires about two-thirds of a gallon of water.
There are several different water delivery methods, but some are better than others, so do some research to see what works best for you. Another important step in conserving water is to use mulch in the vegetable garden and in the landscape to create a barrier against evaporation.
Many people use sprinklers to water their gardens and landscapes, but these are the least efficient tools for watering; the water is not easily directed and evaporation leads to a loss of water. Hand watering is common, and is better than sprinklers, but most gardeners don't have the patience to apply the full amount of water actually required by plants. Sprinklers and hand watering both also may spread diseases because leaves become wet. Use these methods only in the morning to allow plants to dry quickly.
Gardeners increasingly are finding irrigation using soaker hoses or drip irrigation to be efficient and easy. Soaker hoses allow water to weep out of the hose along its entire length. With this method, water is applied at the ground level, reducing the risk of spreading diseases, but it can be difficult to direct water to specific plants or to measure the amount of water used.
The most efficient watering system is drip irrigation, which allows the direct pinpointing of water to specific plants at specified levels (specialized emitters deposit specified amounts of water per hour). This directed approach makes the most efficient use of water, lowering the water bill and saving a valuable natural resource. It can be quite affordable too. Kits for 150-square-foot vegetable gardens and medium-size landscape beds sell for less than $30 each.
What about watering the lawn during dry times? Don't! The cool-season grasses we grow in this region go dormant when it's dry. Just raise the mowing height to about 4 inches or stop mowing (without water, growth slows down or stops). Start mowing again when the rain returns. You'll save on your water bill, conserve water and enjoy a break from mowing the lawn.
John Porter is the WVU Extension Service agent for agriculture and natural resources in Kanawha County. He may be reached at firstname.lastname@example.org or at 304-720-9573. Twitter: @WVUgardenguru.