Texas Red Yucca (Hesperaloe) is a very popular, long blooming succulent that does well in New Mexico landscapes. But the colorful flowers are also a favorite food source for aphids. If left unchecked, aphids will ruin the appearance of the flower spikes and shorten the bloom time of the plant. There is an easy way to get rid of the aphids without the use of pesticides; wash the flowers.
Bring a hose out to the infested plants. Then cup the flower spike from behind with your hand (see photo) and blast off the aphids with a small but hard stream of water created by putting your thumb over the end of the hose. Move your hand and the hose from the top of the flower spike down to its base, knocking the aphids off of the flowers . Do this several times, from top to bottom and wash the flowers clean. Don't turn the hose on too much as a high volume spray can damage the tender flower buds.
Click to watch how to wash off Aphids
To insure the aphids are gone for good, you'll like need to repeat the washing this one more time. Interestingly, the aphids are usually there because small ants "farm" the aphids like livestock, harvesting their sugar-rich honeydew excreted while the aphids feed on the flowers. So the ants will bring the aphids back up onto the flowers after an initial rinse. But after a couple of water spray sessions, they will generally give up and the Hesperaloe flowers will continue to bloom and feed the hummingbirds without the aphids. Or, if you have a heavy infestation, wrap the flower spikes with a little packing tape and this will keep the ants from reintroducing the aphids.
Click to watch how to wrap flower spikes