Help for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
IMPORTANT NOTICE: We are moving to Concord. Our Pleasant Hill location is now closed. We expect to reopen in Concord on Monday, 8/6. Our new address and phone number are:.
UC Master Gardener Program of Contra Costa County
University of California Cooperative Extension
Contra Costa County
Effective 8/6/18, our new address:
2380 Bisso Lane
Concord, CA 94520
and
UC Master Gardener Program Help Desk
Monday-Thursday, 9:00 AM - 12 Noon
Effective 8/6/18, our new phone number:
Tel: (925) 608-6683
Remaining the same:
Email address: ccmg@ucanr.edu
Website: http://ccmg.ucanr.edu
Find us on Facebook: www.facebook.com/CoCoMasterGardeners
Help Desk Client's Request: Three of my Ceanothus Geiseus Horizontalis ‘Diamond Heights' (aka Diamond Heights Carmel Creeper) are turning brown. Tons of brown leaves are falling off. As you can see from the first picture, the one on the left is fine for the most part, but the one on the right is not. The second picture is a closer look of one of the plants with a lot of brown leaves. I increased the watering time from 17 to 22 minutes 4x/week about 2 week ago. This plant gets full sun all day and I live in Concord, CA. Here we get daytime temperatures above 85oF most of the summer. At times we have temperatures above 90oF degrees for several days. I can't tell for sure, but it is possible the one doing well may have a 2-gallon/hour drip and the others may have a 1-gallon/hour drip. I made sure all of them are being watered. What do you recommend in terms of watering? Should I make sure all of them have a 2-gallon/hour drip? Should I trim the very dry branches? Thank you
MGCC Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk with your plant question. You are seeing your Ceanothus griseus horizontalis 'Diamond Heights' turning brown. Unfortunately, this specific ceanothus is not well adapted to the hot summers we experience in Concord (also Central and East County). The plant was originally found in the Diamond Heights neighborhood in San Francisco, and is best grown in conditions like you find in SF: cool and foggy. Along the coast it tolerates full sun, but further inland it requires shade. They also prefer well-draining soil and moderate water.
The brown leaves are an indication the plants have not been getting enough water. If the plant getting twice as much water is doing well, you should be applying that much water to all plants of the same variety. It is best to apply the water less often than four times a week. By applying more at one time, it will go deeper into the soil. Since you are currently watering 4 times a week, multiply the time you water by 4 to get the length of time you need to water once a week. A 2 foot wide Ceanothus 'Diamond Heights' needs at least a gallon of water per week during the hot summer. A 3 foot wide plant would need about a gallon and a half per week. Reduce that amount when the weather cools by watering less frequently, not by cutting the length of time you water.
Dead branches can be pruned out. Check the branch to make sure it's dead before you cut, though. Scrape off a little bark; you should see a greenish wood if it's actually alive. If you see brown or dark tan, the branch is dead.
I hope this information is helpful. Please let us know if you have more questions.
Help Desk of the UC Master Gardener Program of Contra Costa County (SEH)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round to answer your gardening questions. Except for a few holidays, and after our relocation August 6th, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at ,2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683 , email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Biog (//ucanr.edu/blogs/CCMGBlog/)