August, When Water Retention is a Good Thing

By Leslie Watkins

In hot, dry weather and prolonged periods of insufficient rainfall, plants and trees can really suffer. There are measures we can take to protect the valuable investments we’ve made in our gardens. The goal is to get water to the plants and keep it there as long as possible—water retention.

Plants absorb water and minerals through their roots. Moisture moves throughout the plant mixing with carbon dioxide absorbed from the air. Cell structures called chloroplasts contain chlorophyll which convert sunlight into energy. Through the process of photosynthesis plants produce glucose to fuel their growth. Plants cool themselves, and us, by releasing water vapor and oxygen through transpiration. More than 90 percent of water used by the plant is lost through this process. Watering in the evening and early morning gives plants more time to absorb the moisture into their cells.

Things we can do to assist our plants through stressful times of drought include not fertilizing. This results in a slower growth rate and reduces the water needed to support it. Avoid pruning and mow the lawn less frequently to cut down on moisture loss. Hold off on new plantings (because of their need for frequent watering) until cooler weather comes. Remove weeds competing for precious water and deadhead to conserve the plant’s energy that would otherwise be used for reproduction. To further protect themselves, plants may enter into early dormancy and drop buds and leaves, but even when dormant plants still need water.

The number one rule for water retention is obvious—water your plants! Soaker hoses are great for slowly releasing water into the ground and can be moved to where plants need it most. They are inexpensive and come in various lengths to suit your needs. Attach to your hose, arrange the soaker hose around plant roots and turn on the water. Little beads of moisture seep out close to the soil reducing surface evaporation. Watering close to the ground thoroughly encourages deep root growth, resulting in plants with greater drought tolerance. Nice big watering cans are available with an assortment of spouts. Keeping one handy will remind you to water your flowerpots.

The number two rule for water retention—mulch generously. An application of three to four inches of compost, wood chips, shredded bark, leaves, grass clippings or straw will provide a cover that will cut down on evaporation and help cool and protect the living soil. Amending the soil with conditioners like peat moss and compost will improve its structure and increase its ability to retain moisture.

And the third rule for water retention—plant tough, drought tolerant plants that will survive through the best of times and the worst of times. Use these tried and true work horses to provide a strong foundation for your garden. Experiment with the more delicate things later and you will have a higher degree of success, and a lower water bill.

Drought stricken plants may take months, even years to fully recover. Some loss is inevitable. Plants die—even healthy ones won’t last forever. It may be time to pitch that fussy, high maintenance plant. Sad as it may be to lose a favorite plant, it does provide us with the opportunity to try something new, and perhaps more appropriate. Thumbs get greener through experience and experimentation, so don’t give up. Every effort you make creates a connection with nature and contributes to a more sustainable lifestyle.

Top Ten Drought Resistant Plants

• Echinacea purpurea, Purple Cone Flower
• Perovskia atriplicifolia, Russian Sage
• Sedum, Stonecrop
• Nepeta, Catmint
• Agastache foeniculum, Anise hyssop
• Veronica, Speedwell
• Achillea millefolium, Yarrow
• Thymus pseudolanuginosus, Woolly Thyme
• Sempervivum tectorum, Hens and Chicks
• Phlox subulata, Creeping Phlox

Illustration © Leslie Watkins 2016