I have a hopseed bush that I believe is a Monrovia plant. I purchased it a few months ago at Rillito Nursery in Tucson. They sell many of your plants.
I noticed a few days ago that the ends of the plant are turning brown and crispy. The bottom of the plant has really thinned out. The hopseed bush I planted next to it, about 2' away looks fine. I had been watering them maybe 3 times a week, but I have recently started watering less, a deep watering once a week since it is a desert plant. Can you tell me what I might be doing wrong or if the plant may have a disease?
|It sounds like it isn't getting sufficient water or that is showing signs of salt burn. It wasn't clear to me if you planted both bushes at the same time or exactly when that was, but it can be stressful for even desert-adapted plants to be planted at the beginning of summer and establish root systems during the heat. I'll provide you with some basics of watering below:
Desert soil and water both contain salts, which can accumulate in the root zone over time. This salt buildup forms where the water stops penetrating. If you ?sprinkle? plants lightly and frequently or run drip irrigation for short periods, the root ball doesn?t get moistened. Salts will build up in the top layers of soil and damage or kill your plant. Salt burn often shows up first as browning leaves. Deep watering?or leaching?prevents this by flushing the salts past the root zone. It's essential that you allow your drip system (or hose) to run long enough for water to penetrate the appropriate depth. Depending on the size emitters, soil type, etc. this might take several hours or even 10 hours. You can reduce the time you run the system by putting on extra emitters or changing to emitters with higher gallon/hour flow rates. For trees, water should soak 3 feet deep, for shrubs 2 feet, and for annuals, perennials, cacti and succulents, 1 foot. You said you are deep watering but are you sure how far the water is soaking? Use a soil probe (any long, pointed piece of metal or wood to poke into the soil) to check how far water has penetrated. The probe moves easily through moist soil, but stops when it hits hard dry soil.
Here are some watering guidelines for establishing desert-adapted plants from Desert Landscaping for Beginners, published by Arizona Master Gardener Press. Weeks Since Planting 1-2, water every 1-2 days; Weeks 3-4, water every 3-4 days; weeks 5-6, water every 4-6 days; weeks 7-8, water every 7 days. Gradually extend the watering as plants establish. Note these are guidelines, which will vary depending on your soil type, microclimate, etc.
Here are some other possibilities to consider when 2 of the same species planted in the same area and supposedly receiving the same care respond so differently. One may have good drainage and the other have poor drainage. One could be getting more water than the other. The soil could be compacted where one is located. There could be construction debris under one, inhibiting root growth. One could have been root bound when planted so the roots continue wrapping around themselves, inhibiting growth. Did the roots dry out before transplanting? Was there any damage to the roots? Has there been any construction activity near the plant? Heavy equipment compacts the soil and can damage roots. Have you applied any weed killer nearby? Any chemical drift from the neighborhood? Transplant shock is a possibility. Sometimes one plant is just not as healthy as another.
Hopbush is not susceptible to much in the way of disease or insect problems, but you might want to take a sample back to the nursery to see if they can diagnose something in particular. Good luck!