The Silver King, with friends.

Tolerating the Palm Springs summer heat poses a challenge to any living thing—but box-leaf shrubs (euonymus), including the Silver King (see last week’s column), are up to the challenge.

These plants enjoy good potting soil, but can tolerate less-rich soils and moderate watering. Since the shrub is easily pruned, it can serve as an excellent topiary specimen. If it has a good center trunk, it can be shaped up into a small tree over a couple years.

When you visit your nursery to select a plant, compare the size of a one-gallon plant with a five-gallon plant. Be sure whichever you choose is well-rooted: You should be able to see a few roots through the holes in the can. Since they are not super-fast growers, select the size that will give you satisfaction now!

  • Take the plant home, and water it well—water should come out through the holes in the can. Prepare your pot by placing it in its permanent location.
  • Fill your pot after covering the drainage hole with screening or a folded coffee filter. Bring the soil level up about half way, and then compress the soil.
  • Add a large handful of time-release fertilizer to the soil. Leave a cavity in which to place the root ball.
  • Carefully remove the plant from the container by turning it on its side; compress the container to loosen the root ball; and gently urge the entire plant out from the can, being cautious to not tear the stems from the roots.
  • Loosen the root ball’s mass by opening it with your hands or a small trowel. You do not need to be overly cautious at this point.
  • Place the plant into the pot and add soil, making sure the end result will place the top of the plant’s root ball about 2 inches below the top of the pot.
  • Add more soil, and continue to pack it in around the root ball. Bring the new soil level up even with the top of the plant’s root ball. Do not bury the root ball under new soil. Pack the entire mass firmly, and water in thoroughly.
  • Be sure your newly planted shrub does not dry out. During the first two weeks, you may need to water daily. Depending on sun exposure, heat levels and wind, you might be able to drop back to every other day.

Prune shrubs in the spring after flowering (inconsequential) to maintain the desired shape and to remove green shoots that will sometimes pop up. It’s proper to remove a quarter to a third of the shrub each time it is pruned, forcing new growth to come from old wood deeper inside the canopy of the shrub. This rejuvenates the shrub, adds more new growth to the canopy, and keeps it young and vigorous.

One of the main issues with the euonymus is its tendency to get powdery mildew. Although this is less likely to occur in the dry desert, reduce the likelihood by choosing a location with morning to mid-afternoon sun, and good air circulation; water it in the morning.

Marylee Pangman is the founder and former owner of The Contained Gardener in Tucson, Ariz. She has become known as the Desert’s Potted Garden Expert. Marylee is available for digital consultations, and you can email her with comments and questions at potteddesert@gmail.com; follow the Potted Desert on Facebook.