A Modern Phoenix exclusive
How to remove your midcentury grass lawn
By Scott McMahon, arborist and curator of trees and succulents at the Desert Botanical Garden of Phoenix
The steps to eliminate a lawn are pretty basic and successful if adhered to properly. The lawn must be healthy and growing well. Late summer/early fall is the best time to spray with Roundup. Use the concentrate and the original formulation, not the newer one that has Diquat. A quart will cost about $40.
A two to three gallon hand sprayer will cost an additional $40. I like the Solo, because it has more plastic parts, which don't corrode as easily. Both can be found at Home Depot.
Apply the material at the label rate, soaking the grass thoroughly. For much larger applications, a power sprayer will be better, depending on the size of the lawn. Roundup will take a minimum of 7-10 days in warm weather to start working. The grass can be removed after the top has died and any rhizomes dug up have a purple color to them. The turf can be tilled and the root material taken away, but be prepared for regrowth of stubborn areas, which can be spot sprayed with a quart spray bottle.
My own lawn wasn't completely dead until a year had passed. If you're not persistent with the regrowth, it will spread again and become a problem. Roundup is safe to use and not active in the soil. It can be used around cacti and other succulents, because it is not a contact herbicide, rather working once reaching the root system, and these plants won't take up enough to be effective. It is non-selective, killing broadleaf as well as grasses, but is extremely effective on Bermudagrass and Johnsongrass and other perennial grasses. It has been around for at least 30 years and is still the best product for these types of weeds.
The non-chemical approach would be simply tillage and removal, then digging up any regrowth, until satisfied all rhizomes have been eliminated. Much more physical work with ensuing labor costs if not willing to do it yourself.
In both cases, do not try to convert to a desert landscape too soon, as regrowth is a definite possibility.
Never use plastic under granite, because the grass can punch through it, and the plastic will inhibit root growth of neighboring plants, souring the soil.