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
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/).
Advice from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Thank you for contacting the Help Desk of the UC Master Gardener Program of Contra Costa County. Your recent email had three related questions:
1. Growing watermelons and tomatoes in large containers…what is the best soil composition for successful growth?
2. What type of soil is best for your tomatoes that will be grown in wine barrels in 8 hours of hot sun?
3. Your compost material has lots of worms in it. The compost will be mixed into a wine barrel in the hot sun. How can you keep the worms alive and well in wine barrels planters in full sun?
Here are some additional thoughts about each approach as well as some notes on the benefits and disadvantages of each approach.
Soil, sand, compost and coconut coir. If you use this approach, it would be best to use a loamy garden soil. Silty loam would be the best. Sandy loam could be used, but in that case you should use less sand in the mixture. Clay soils are generally avoided for watermelon culture because they drain poorly, but they can be productive if irrigated with care to prevent prolonged saturation of the root zone (a condition that favors the development of root rot pathogens) and to allow good drainage between irrigations. Adding plenty of organic matter (e.g., compost or coconut coir) would make both the clay and sandy soils more productive.
If you use garden soil, keep in mind that it can contain insects, weed seeds and disease organisms. For this reason, it would be best to heat the soil in an oven for 1 hour at 210°F to kill any bacteria, fungi, insects, or weed seeds before the soil is combined with the compost and sand.
This soil mixture will be heavier than the commercial potting mixture. Added weight is sometimes a disadvantage for containers. However, since the containers may become a bit top heavy if you have a good crop of large watermelons or tomatoes growing upward on a support structure, the added weight could be an advantage. If you want the planter to be lighter, you could replace the sand in the mixture with either perlite or vermiculite. Those amendments will aid in drainage just as the sand does but would produce a mixture that weighs less than one that includes sand.
Commercial Soil Mixture Combined With Compost And Coconut Coir. Usually a commercial soil mixture does not include any actual soil, but they can still provide a very good growing medium. If you use an available commercial soiless mixture, it would probably not be necessary to add either compost or coconut coir. This commercial mixture's ingredients already include compost, and the peat moss would function in much the same way as coconut coir to improve water retention. Adding compost and coconut coir wouldn't detract but would add to the cost.
One disadvantage of the mixture is that it uses peat moss which is less sustainable than the coconut coir alternative. Peat comes from very slow-growing, slow rotting plants and it typically takes 1,000 years for a bog to add 1 yard to its depth. Coconut coir is a byproduct of the coconut industry and is more easily renewed than peat.
If you want to make your own potting mixture that does not include garden soil or peat moss, you can use a combination of one-third each of compost, vermiculite or perlite and coconut coir. Measure the volume of the coconut coir only after it has been soaked in water since its volume will increase significantly once it absorbs the water. I've have been regularly growing vegetables in containers for many years and always use this potting mixture. It would work well for both the tomatoes and the watermelons.
For additional information on growing watermelons, I suggest you look over the information found at:http://anrcatalog.ucanr.edu/pdf/7213.pdf . For information about growing tomatoes in containers, see http://ccmg.ucanr.edu/files/229047.pdf.
Compost Worms In Containers. In our research, there are varying opinions about the viability of worms in containers. Considering that you mentioned having worms in your containers that will be in the hot sun for 8 hours per day, the worms would not survive in this environment. They prefer moist, cool soil which might be hard to manage in your situation. However, experimentation is always a great learning experience (although maybe not for the worms). For example, you could consider using some shade protection on very hot days. Possibly you could set it up in a way that shades the container but not the plants. Also, be sure that the soil mixture has plenty of peat and/or coconut coir to help retain water.
Thank you for contacting the Help Desk. Feel free to check back with us if you have additional questions.
Help Desk of the UC Master Gardeners Program of Contra Costa County (tkl)
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/).
Client's Request: Client is growing tomatoes in a community garden. Several of the client's tomato plants are now droopy, appear diseased on the stems and leaves, and not performing as expected. Client dropped off a sample of the tomato plant (leaf and stem) at a Farmers' Market Master Gardener Help Desk. It was then delivered to the MGCC Pleasant Hill office for a Help Desk analysis of the problem (s?) and recommendations of what to do next.
MGCC Help Desk Response and Advice: We were able to determine what was going on with your tomato sample by viewing it under our microscope. We found spider mite infestations, but that is secondary to what is actually going on with the plant. We believe that the tomato plant is suffering from "pith necrosis". While Master Gardeners have seen some previous evidence of this tomato disease, it is so far rarely seen in California, and UC does not have very much information or recommendation on the disease. However, Ohio State University has a Fact Sheet that provides information on the disease and its management. http://u.osu.edu/vegetablediseasefacts/tomato-diseases/tomato-pith-necrosis/. From our reading of the Fact Sheet, it doesn't appear that there is much you can do to manage the disease at this point in the tomato growing season, but you should consider your cultural practices before planting in the same plot next year (e.g., crop rotation, fertilization, etc.). The OSU Fact provides the best guidance we have at this time.
Thanks for contacting us and providing the sample.
Help Desk of the Master Gardeners of Contra Costa County
Note: The Master Gardeners 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/
/span>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
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/
- Author: MaryJo Smith
Saturday was Day One of the Great Tomato Plant Sale in Walnut Creek. Tomato lovers, young and not-as-young, formed a line that snaked around the corner and down the street as they waited for the sale to begin. The garden was abuzz with activity as CCMG volunteers set up the tents and tables, did plant inspections, and found their stations. The help desk tent was ready to answer questions about tomatoes, gardening, or the Master Gardeners' programs; the garden guides were ready to help with location and selection of tomatoes and other veggies; the expeditors were posted at the end of the garden to guide the customers through the checkout process; and the cashiers and CI's were at the registers to ring up the purchases.
The gates opened promptly at 10:00 am. Customers, with lists in hand, focused on finding the tomatoes they had carefully selected from the myriad of varieties offered, for their gardens this year. For the next two hours, there was a frenzy of tomato buying. There were flats, there were bags, there were bins, there were carts, and there were wagons. It was amazing. I manned one of the cash registers and by the third hour, I think I had rung up over 900 plants. The seven other cashiers were also ringing up about the same amount. The pace continued, with only a few lulls when many of the attendees stopped to listen to Our Garden's Janet Miller, give presentations on growing tomatoes and other veggies. It was a great turnout!
Even after selling so many plants, believe it or not, we still have lots of inventory at both locations and they are definitely not “left-overs.” While we sold out of a few varieties, we still have over 3,500 tomato plants at Our Garden. And, we've set aside 3,000 plants for the upcoming West County sale.
So, if you missed the first day of the GTPS, don't despair – Our Garden will have plants -- tomatoes (of course!), peppers, various other veggies and herbs, beans, and even some flowers -- available this Wednesday and upcoming Saturday, and West County will have its very own sale on Saturday as well. CCMG volunteers will be on hand to help you out.
Come check it out!