Q: I live in Tucson. Alkaline soil, lots of sun, not much rain. I have found contradictory info on fertilizing Tecomas. Local websites either say “responds well to regular fertilizer,” “fertilize with ammonium sulfate” or “this plant particularly hates (fertilizer).” Does anyone have a decisive answer from a reliable source?
A: Tecoma stans, aka yellow bells, has a reputation as a tough plant that needs little help once established, except for occasional pruning and pest management. Although I couldn’t find any research detailing its exact needs, all plants need water and nutrients.
If you want to have your soil tested by a laboratory, many of them will make fertilizer recommendations based on the results and which plants you are planning to grow. If you would rather experiment without a soil test, I recommend a slow release tree and shrub fertilizer in the spring and also recommend regularly scheduled drip irrigation every two or three weeks unless it is raining.
You can use composted manure or another organic material that has been composted as a slow-release fertilizer. In the end, your plants will help you figure out their needs by how well they appear and grow. For example, plants that begin to have yellow leaves with green veins are often showing a sign of nutrient deficiency. Taking a look at your landscape plants once a week or so to see if problems are occurring is one of the cornerstones of integrated pest management and a great way to catch problems before they get out of hand.
Peter L. Warren is the Forest Health Program Coordinator for the Arizona Department of Forestry and Fire Management. Questions, photos and videos may be emailed to tucsongardensage@gmail.com
