Drought Gardening

Marlena Hirsch

During periods of drought, we have responsibilities to conserve water by planting landscapes that use plants adapted to our dry summer climates. Our native plants from an oak woodland or chapparal ecosystem evolved with dry summers.  If we chose these kinds of native plants, they don’t need summer water when they are established.  We are also helping “the little things that run the world.”(E. O. Wilson)  The little things like caterpillars are food for baby birds.  Most caterpillars feed on plants that they have evolved with.  Native plants are essential for them.  If you grow native plants, you are enhancing the life around you, instead of growing introduced non-native plants that require more water and do not support wildlife. Plants that evolved from other parts of the world often make a sterile environment. 

Growing native plants conserves water and supports wildlife making a rich ecosystem with delightful visitors like birds and butterflies. I am especially thrilled with the elderberries that we planted.  Their four to five months of big creamy blossoms makes four to five months of berries for the birds.  The big band-tailed pigeons (a native species) are quite a sight balancing on the slender branch ends to reach the berries.

Using native plants that are the same as the species that grow in the area works best in a drought tolerant garden.  The nursery trade sometimes breeds a native species for showy flowers, and the selection may lose is adaptability to the environment.  For example, I have tried to grow the hybrid monkey flower bushes with no success.  My garden now has the native species that do well.

There are tricks to growing natives.  Plant native plants in October when the winter rains will water the plants.  If there are warm days with no rain during the first few months, the plants may need to be watered with a hose.  This is to be sure the root ball does not dry out and the plant dies before it can get it roots into the soil.  In our climate, the ground is usually well soaked by mid-November.  Watering each plant is not likely except a few times depending on weather.  The other tricks are no soil amendments needed and no drip lines are needed.  Mulch is needed. 

Drought tolerant plants with mulch are key to less irrigation.  If you have not used mulch to conserve water in the garden, it acts as a blanket that seals in moisture.  A mulch of about 4 inches, keeps in moisture and stops weed seed from sprouting.  Some weed seed blows in on top of the mulch, so those weeds need to be removed, but overall, much is good for both weed control and saving water. Mulches made of wood were tested for flammability, and Arbor mulch, partly composted wood chips, is the safest one.

Summer water will get the roots established during the first summer. The plants need an hour or more of sprinkling every month or six weeks.  A sprinkler is more like natural rain and works better than a drip system for native plants.  The next summer they can go longer without water.  Another way to think of the summer watering is to make sure that June gave the plants a good rain or water with a sprinkler.  Let the plants go without water until September.  You are giving the native plants a dry summer, but with a little help at the end and beginning of the rainy season. 

Lawns need regular water to stay green.  If that look is desired, there are grasses and sedges that can give a lawn effect with no summer water.  Carex mansa can be mowed at the highest setting on the mower and stays green till mid-June.  If not irrigated or mowed, it lays flat, so it is not going to carry a fire up into shrubs and trees.  I have let lawns of deep-rooted perennial grasses go dormant with no summer water, and had them turn green when the rains start. Some gardens use patches of gravel of different colors for a lawn effect.  A flat space of pebbles ringed with bigger rock and plants gives an effect similar to a lawn or water feature.

I have my favorite plants and some are not native to here, but native to a similar dry-summer climate like South Africa or Australia.  I mix them into the landscape.  I also have plants that I admire because they survived the fire.  For example, there is a clump of canna lilies, near our sidewalk.  That is a tropical moisture loving plant.  Its roots have found our septic system’s leach line and it needs no water.  This area also has non-native succulents near the house, for a fire-resistant planting closest to the house.  Our gardens are for us to enjoy and plant choice is often personal.