Advice from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Subject: Summer Tomato Problems
Client: Came to our Help Desk office with multiple problems with his tomatoes and maybe on his samples of rosemary and rhododendron
First, we discussed the early blight problem on your tomato plants. In particular, we discussed that spores of the early blight fungus in your case were spread by splashing water, so it is important to keep the leaves as dry as possible. We also discussed using mulch to reduce the spread of spores from old infected leaf material in the soil, and using crop rotation techniques. Here is a link to additional information and photographs http://ipm.ucanr.edu/PMG/GARDEN/VEGES/DISEASES/tomearlyblight.html.
We further identified a disfigurement on the bottom of the tomato fruit as a physiological problem called catfacing. It occurs when weather is too cold during flowering. There is not any way to prevent this but the problem will not spread and the fruits are safe to eat. A link to that information is here http://ipm.ucanr.edu/PMG/GARDEN/VEGES/ENVIRON/catfacing.html
Finally, I looked at the specimens of rosemary and rhododendron leaves you brought in, and confirmed that there were no pests or diseases there. However, both plants appear to be water stressed and should perk up with additional irrigation.
I hope that this information is helpful. Please do not hesitate to ask for advice again. We are here to help.
Help Desk of the UC Master Gardener Program of Contra Costa County (JL)
(all pictures from UCANR links cited above)
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, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, 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 Blog (http://ucanr.edu/blogs/CCMGBlog/).
Advice from the Help Desk of the
UC Master Gardeners Program of Contra Costa County
Client: I'm having some early summer problems in my garden. I'm reluctant to use pesticides in my garden since I have several small children. Would you please provide some recommendations to either cure and/or minimize the problems:
- Tomato plants are doing reasonably well but there are some funky looking lower leaves that I'm concerned about.
- My roses' leaves are mottled with brown-red markings.
- The flowering pear tree's leaves are mottled and dropping; an arborist recommended injecting a chemical into the tree to cure the problem
- I suspect that my garden soil is too alkaline (i.e. previously tested pH@7.1). How can I test it and what can I do to reduce pH? Will just adding compost reduce pH?
UCMGP's Help Desk Response: Thank you for the photographs, which were very helpful. Our responses follow:
Flowering Pear Tree: The photograph from the flowering pear confirms that it is infected with Entomosporium, another fungus that is spread by splashing rain. http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/DISEASES/entomoslfspt.html. We do not think that this disease warrants fungicide treatment. I do not know what chemical the pest company was
all pictures from ucanr.edu
Soil pH: Home test kits for soil are fairly reliable as long as the instructions are followed carefully. A pH of 7 - 7.5 is borderline satisfactory, but may go up over time because our municipal water tends to have high pH. We recommend that you wait until the plants have been harvested and then add garden sulfur to the soil in the fall according to label directions. Lowering the pH with sulfur takes time (i.e., months), so you must be patient. Adding compost will not lower the soil pH.
I hope that this information is helpful. Please do not hesitate to contact us again. Good luck on a successful summer garden.
Editor's Notes: It is likely that the tomato, rose, and flowering pear tree problems may have been caused by the late rains creating conditions conducive to fungus: cool, humid conditions. Warmer, drier weather should minimize these types of fungus infestations provided there is adequate air circulation and not overhead watering early evening.
Help Desk of the UC Master Gardener Program of Contra Costa County (JL)
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, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, 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 Blog (http://ucanr.edu/blogs/CCMGBlog/).
![tomato leaf w/early blight tomato leaf w/early blight](http://ucanr.edu/blogs/CCMGBlog/blogfiles/30053.jpg)
Response from MGCC's Help Desk: After further examining the tomato specimen that you brought to Our Garden' AAMG Help Desk yesterday in our Pleasant Hill Help
![tomato stem w/early blight tomato stem w/early blight](http://ucanr.edu/blogs/CCMGBlog/blogfiles/30054.jpg)
![tomato w/early blight tomato w/early blight](http://ucanr.edu/blogs/CCMGBlog/blogfiles/30055.jpg)
Legend Tomato
OP (open-pollinated), determinate, 68 days, red, beefsteak (14-16 ounces), resistance: early blight, late blight (We had this variety at our tomato sale this year.)
Manalucie Tomato
Hybrid, indeterminate, 82 days, red, globe, resistance: blossom end rot, gray leaf mold, early blight, fusarium wilt
Matt's Wild Cherry Tomato
Heirloom, indeterminate, 70 days, red, cherry (1/2 inch), resistance: early blight
Mountain Fresh Plus Tomato
Hybrid, determinate, 77 days, red, globe (12 ounces), disease resistance: VFFN, blossom end rot, early blight
Mountain Supreme
Hybrid, determinate, 69-70 days, red, globe, resistance: VF, blight
Old Brooks Tomato
Heirloom, indeterminate, 78 days, red, globe (6-8 ounces), resistance: blossom end rot, early blight, late blight
Tommy Toe Tomato
Heirloom, indeterminate, 70 days, red, cherry (1 inch)
Master Gardeners of Contra Costa Help Desk
Note: The Contra Costa Master Gardener Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/