Regional Gardening Reports :: National Gardening Association

In the Garden:
Southwestern Deserts
March, 2008
Regional Report

Share |

Leafcutter bees neatly trimmed cuttings from this pink trumpet vine to line their nests.

Spring Cleaning

There seems to be a small window of opportunity to spruce up scraggly plants before rampant spring growth begins. I've had my eye on frost-damaged lantana and a sprawling trumpet vine, waiting for the first signs of new growth before trimming. I wait and wait, and then the week that I turn my back, they both go berserk.

White lantana in my front courtyard has looked ragged since a winter freeze, but it's best to leave dead foliage on the plant to act as insulation for another freeze. Damage usually looks worse than it is, so pruning too early increases the risk of cutting away more than is necessary. When the sun finally started lingering on this patch of ground last week, the lantana sprouted like crazy, filling entire dead-looking branches with tiny shoots. All I had to do was tidy a few broken tips.

Pink trumpet vine is a slightly different clean-up story. It is semievergreen, meaning it might drop some leaves if temperatures get cold enough. Located on a warm wall, my vine typically retains considerable greenery through the winter. It always produces a "grow-like-crazy" phase in the early fall when it overpowers its trellis and sends 15-foot branches rudely sprawling across other plants. During this phase, it is filled with pink flowers that attract hummingbirds and other pollinators, so I let it misbehave. During winter I like the greenery it offers; sometimes it continues to bloom quite late, so I still don't corral its long, whip-like vines. All of which means spring-cleanup can be lengthy.

When the vine started leafing out a week ago, it was obvious that some of the old growth was dead and needed to be removed. The way vines intertwine can make it tricky to decide where to cut. Let's see, which branch is truly a goner and which is attached to green growth 10 feet away? As I was poking through the branches, I came across a branch that had been plundered by leafcutter bees.

Female leafcutter bees neatly cut half-moon shapes from leaf or petal edges to line their nests. Thin, smooth surfaces such as rose petals, bougainvillea, and trumpet vine leaves seem to be preferred. Who doesn't like a soft bed? A bee finds a hole slightly larger than herself, often in the ground or wood. She inserts several curled pieces of plant material to form a protective "cell." Then she fills the cell with a mixture of pollen and nectar to nourish the hatching larva. Finally, she lays one egg, seals the cell with more plant material, and is ready to repeat the process. Leafcutters are 1/4- to 1/2-inch long, black or grey, and they resemble honeybees. They are solitary creatures and ignore humans. The bits of foliage they remove do not harm healthy plants so no control is needed. I have to admire their handiwork: the cuts they make are so precise!

Care to share your gardening thoughts, insights, triumphs, or disappointments with your fellow gardening enthusiasts? Join the lively discussions on our FaceBook page and receive free daily tips!


Today's site banner is by Marilyn and is called "Salvia regla 'Royal'"