QuestionWe live in Phoenix and recently had to remove 3 oleander bushes because their roots got into the sewer pipes 5' below ground and were causing us all kinds of high $ plumbing problems. We're seeking attractive, low maintenance replacements with shallow root systems that won't cause us the same problem in a few years. We looked at cape honeysuckle but I found a post where you said it also has a deep root system. Do you have any suggestions for us? We don't want cacti, yucca or succulents for this location. Thanks~!
AnswerHi Mar,
thanx for your question. I lived in Phoenix for a couple of years many moons ago. Here's the problem. In the desert, plants are generally shallow rooted because of lack of regular rain. Roots will generally go very deep so the plant can always find a source of water otherwise it would dry up and die. Some cacti and other plants have a deep tap root that helps the plant survive even the driest years. I'm afraid most shrubs (especially desert shrubs) may have highly invasive roots.
Here is a link to the dwarf poinciana or red bird-of-paradise plant which can be grown as a perennial or annual. It will probably die back to the ground in Southern Arizona and will not be hardy in zones cooler than USDA Zone 8a. It may not have as invasive of roots because it is a subtropical plant as opposed to being a true desert plant although it does tolerate heat and drought. It is a beautiful member of the legume family and easily started from seed.
http://ag.arizona.edu/pima/gardening/aridplants/Caesalpinia_pulcherrima.html
I'm going to refer you to the University of Arizona Cooperative Extension Service. They have a Master Gardener Program and you can locate the people for your county in this link.
http://cals.arizona.edu/extension/mastergardener/index.html
I also recommend High County Gardens out of New Mexico. They specialize in xeriscaping (landscaping for hot, dry areas) and I have had superb experience with them.
http://www.highcountrygardens.com/
I hope this helps.
Tom
