Colorado Mountain Gardener: TIPS TO CONSERVE WATER IN THE VEGETABLE GARDEN

By Yvette Henson, San Miguel Basin, CSU Extension

Colorado has a semi-arid to arid climate with recurring periods of drought. Yet, plants in the landscape provide many benefits like cooling the air temperature around and inside our homes. There are also physical and mental health benefits from growing gardens. Growing at least some of our own food contributes greatly to food security. So, how do we use water responsibly to grow a garden, without waste?

This blog posts gives some tips to conserve water in the vegetable garden:

· Grow only what you need.

· Group plants with similar water needs.

· Plant in blocks, not rows, to shade the soil.

· Incorporate organic matter into soil before planting to hold water.

· Apply mulch, after planting, to reduce evaporation.

· Cover plantings with row cover fabric to reduce evapotranspiration.

A freshly watered vegetable garden. This garden will benefit from an application of mulch to the fall peas to reduce evapotranspiration.

Some other water conservation ideas to investigate are Hugelkultur, planting in natural depressions and paths of runoff (“rain gardens”). Or you can create your own depressions, swales, and underground trenches to direct water. Check water law before creating ponds or other larger water holding/directing structures.

“waffle gardens,” depressions in the ground hold water for crops, and were used by first nations peoples in the southwest. (Photo credit: Jodi Torpey)

When watering your garden:

· Water only when needed, rather than on a schedule.

· Use a trowel or shovel to check soil moisture, rather than guessing.

· Water more deeply, to depth of the root zone, less frequently.

· Water slow-draining soils, like clay, in several short intervals to reduce runoff.

· Water during the coolest times of day or when your garden is shaded.

· Don’t water when it is extremely windy.

· Don’t water automatically when you’ve received adequate rainfall (> ½”)

· Use soaker hoses or drip irrigation.

· Use harvested rainwater (see this Fact Sheet https://extension.colostate.edu/topic-areas/natural-resources/rainwater-collection-colorado-6-707/ )

In general, water is most critical during the first few weeks of development, immediately after transplanting, and during flowering and fruit production. Young plants need less but more frequent watering. Older plants use more water but need it less frequently. They have deeper roots and larger canopy.

You can target the timing and amount of water to add during the most critical periods of each specific crop.

Root crops need water most when roots are sizing up. Water stress can cause bolting and/or strong flavor. Fruit- and seed-bearing crops need extra water when fruit is setting and filling. Too little water can reduce yield significantly but can also make fruit more flavorful. Too much water before fruit set can delay it. Bulb crops, like onions and garlic, need more water when young and less water when maturing and none when curing (in ground).

Certain plants require more water than others. Are they worth it? For example, beans and strawberries (especially when establishing) need 0.25 to over 0.50 inches of water per day when blooming and setting fruit. Of course, this is variety dependent. Certain beans, like terpary beans, do not require much water.