Skip to main content

Soil, Mulch & Compost

Healthy plants start with healthy soil. So, before planting or installing an irrigation system, make sure to test your soil, and then add amendments and mulch as appropriate to create a healthy    environment for your water conserving plants.

Compost (PDF)

Mulch (PDF)

The Squeeze Test (PDF)


As you gain an understanding of your soil, you will also be able to schedule your irrigation with more efficiency and provide your garden with the right amount of water.

First, get to know your soil; this can mean the difference between enjoying the fruits of your labor - a garden, full of healthy and vigorous plants; and the alternative - facing the realization that you have wasted time, effort and money, adding unnecessary amendments to the soil in your garden.
Soils fall into one of three categories: clay soils, sandy soils, and loam soils.


Sandy Soil
Easy to cultivate and drains well so the plants do not stand with their roots in water for too long. However, as it drains quickly, plants need to be regularly watered and fed if they are to thrive.

Clay Soil
Weighty to lift and difficult to work. Drainage is usually bad; the soil clings to the feet in wet weather. Will drain slowly or not at all.

Loamy Soil
Contains sand, silt and clay, in such well-balanced proportions that none produces a dominating influence. These are amongst the most fertile soils. Watering frequency will also be moderate compared to clay or sand.

To determine which type of soil you have, do the squeeze test.

Next, till the soil. Tilling reduces soil compaction, adds air capacity and enhances drainage capabilities. Begin with deep spading, plowing or tilling the earth – to a depth of about six inches – to break up compacted soil and allow root systems to grow deeper into the earth, where they have greater protection from drought.

Third, add amendments, if appropriate. Amendments can include compost, fertilizer and mulch. Note of caution: not all water conserving gardens need mulch or fertilizer and adding them inappropriately can hurt your plants. Consult a horticulturalist to determine if your soil will benefit from amending.