How to Reduce Water Use in a Condominium HOA; Part 2.

 In How to Reduce Water Use in a Condominium HOA; Part 1 you determined what plant water use category you are in; 

Landscape water use categories

0-2 feet of water covering the irrigated landscaped area (nice job!)

3-4 feet of water covering the irrigated landscaped area (not bad)

5-6 feet of water covering the irrigated landscaped area (too much water used, scale back!)

Cranking the Water Use Down

If you are not happy with your landscape water use, or want to save even more water than you have, first consider eliminating trees above the roofline of the condos or at least pruning them lower. Are large trees important? Yes they are but perhaps not nearly as important as the cost of the water they need to survive.

These pine trees are planted too close but the shade they produce can't be denied. As these pine trees get larger, the cost of watering them may be worth more than the shade they produce. It will be up to you but consider removing them after replacement trees have been established.

Big Trees Use More Water than Little Trees

It may sound comical but people buy trees that grow 50 feet tall and only need a tree that is 15 feet tall (single story homes). Examples are pine trees. Sure pine trees may not use as much water as a mulberry but it still uses water. The bigger it grows, the more water it needs. Plant or keep trees that shade the walls and windows on the south and west sides of a building.

This hot, west facing exterior wall has four small shrubs that create no shade on the wall but still require water. Their distance apart (about 10 feet) would provide the water needed to plant and locate three small trees or shrubs (ten feet tall) that would shade this hot wall. As the plants we chose to replace them got larger, more water should be added. Add one more small tree (patio tree) to provide shade for the patio area walls and door.

Selecting "Backbone" Trees and Large Shrubs

Selection of "backbone" trees and shrubs should be hardy, deciduous, and survive temperatures to at least 20F during the winter. What are backbone trees and shrubs? These are trees and shrubs you don't want to lose to winter freezes. The trees and shrubs should be deciduous because we want the sun to warm this condo in mid-winter. If you want to save even more water, use small deciduous desert (xeric) trees and water them separately from the more frequently watered mesic plants. 

Landscape "Negative Space"

The fewer plants used and the smaller they are will, for the most part, determine how much water your landscape uses. Deserts use less water by NOT growing plants. I call not planting.... "negative space". Where are plants needed? Where are plants NOT needed? Leaves these spaces open. Creative use of negative space is challenging. In the wetter, eastern US lawns were used to occupy negative space. In the desert we must be more creative; boulders, changes in rock size (texture), changes in elevation, artwork, wall paintings...all can be important when not using water.

Dry washes can use textural changes along with plants. Rocks don't use water.

Open spaces don't use any water and the plants used were desert in origin (xeric) so they aren't watered very often. I would substitute small trees near the windows.

Textural change in the mulch and wall paintings add color and interest to an otherwise somber area and don't use any water. What is the water use here?

Planting in Desert Soil

Locations of ten foot tall trees or shrubs should be 4 to 5 feet from the home. Taller trees and shrubs can be planted further away. 

Soil amendments should be lightly mixed with the soil at planting time along with water. 

Planting holes should be wide and not necessarily deep unless there is a clear drainage problem. If a slight drainage problem exists, plant on a mound of amended soil rather than digging deep.

Water should be applied away from the foundation of the home. In the desert, plant roots follow where water is applied.

Trees and shrubs should be fertilized once in the spring. Two times at most. Showy plants are fertilized three or four times a year and when they flower best.

Trees use water. Bigger trees use more water. Lots of big trees use lots of water