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.
Pith Necrosis pictures from OSU Fact Sheet
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.
on tomato plant
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/
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!
How Do You Decide in Only Five Minutes?
Tips from Liz Rottger
With nearly sixty heirloom tomato varieties in this year's Contra Costa Master Gardeners Great Tomato Plant Sale, where do you start? With so many one-of-a-kind heirloom tomatoes to choose from, how do you decide which variety to buy?
First, you need to decide which variety will grow well in your location. Do you live in cooler location in West Contra Costa? Or, in hot, dry East County? Do you have limited space and want to grow tomatoes that grow well in containers? Are you intrigued by some of the new varieties we are offering this year? Or, are you a dyed in-the-wool traditionalist and just want those large, juicy beefsteaks? Or, maybe you're a pasta fan and want a freezer-full of homemade pasta sauce next winter.
For a successful tomato plant that will produce lots of wonderful fruits throughout the season you need to think first about where you are planting it. Choose a variety that fits with your micro-climate and space requirements. Here are some varieties that fit the two major climate types in Contra Costa.;
For our Cooler Climes Buyers:
- Legend—blight-resistant, well- adapted to cooler climes, it will be the earliest-maturing slicer in your garden.
- Gold Nugget—developed at OSU–where else for cooler climes?—these ¾” golden cherries will mature in only 60 days, continue from early season ‘til frost and have a rich, sweet flavor.
- Sophie's Choice—in 65 days this slicer tomato is one of the earliest bearing varieties and produces large, flavorful fruits. It actually doesn't like heat.
- Stupice—a very cold-tolerant, disease-resistant and early tomato with delicious, 3-4 oz. fruits in clusters.
For Hot, Dry Climate Buyers, here are some varieties that need lots of heat:
- Boxcar Willie—10-to-16 oz. tomatoes with a rich, sweet flavor and just a touch of acid for tanginess.
- Hawaiian Pineapple—the name says it all, these large, yellow, 1-pound tomatoes are sweet and fruity.
- Kellogg's Breakfast—a classic, large orange beefsteak tomato weighing up to one pound.
- San Marzano Gigante—a prolific, classic pasta tomato with enormous, meaty fruits.
Now, there are other considerations when buying tomatoes. You'll want to think about what you want out of your tomato plant. Do you want a rich pasta sauce or a slicer for delicious BLTs or a ton of small cherries for the grandkids? To make your job a bit easier, we've made up a few shopping lists for different kinds of buyers: traditionalist, canning and sauce cooks, the avant-garde buyer and the gardener with little or no space. Here they are:
Traditionalist Buyers, here are some of our trusted and much-loved stand-bys:
- Bloody Butcher—with a name like that, you better be sensational and it is! High-yielding, dark red and delicious!
- Brandywine Pink—one of American Classics, some consider the best tasting tomato ever.
- Cherokee Purple—Pre-1890's heirloom with a delicious, old-timey flavor.
- Isis Candy—gorgeous bi-color cherry in heavy clusters, one of our personal favorites.
- Mortgage Lifter— the legendary large (1-2 pounds!), tasty beefsteak on very productive, disease-resistant plants.
- Sungold—positively luscious, apricot-orange cherries borne on beautiful, 15” long trusses. A visual eye-candy that you can actually eat in your garden!
- Amish Paste—one of the largest sauce tomatoes, excellent flavor and tolerates cooler climes.
- Opalka—a single tomato can make an entire rich tomato sauce, so meaty is its flesh.
- Pompeii—very productive Italian plum tomato with rich, meaty flesh.
- San Marzano—the most famous Italian sauce tomato with a thick, dry, almost seedless flesh.
For avant-garde Buyers looking for a new variety, here are some of the “New in 2015” varieties:
- Baylor Paste—so abundant that you'll have a tough time just keeping up with picking this delicious paste tomato.
- Czech's Bush—masses of 4-8 oz. fruit clusters, coming on early and bearing long.
- Sun Sugar—fruity-tasting orange cherry tomatoes which produce in beautiful clusters on vigorous vines.
- Pomodoro Canestrino di Lucca—direct from Italy a classic pasta tomato that is also great in salads.
For our Buyers with a postage-stamp size yards, here are some varieties that you can squeeze in any sunny spot:
- Lizzano—ideal for hanging baskets and containers, a cherry with a non-stop harvest of 1” fruits, perfect for snacks and salads.
- Nebraska Wedding—the best thing to come out of Nebraska since Dick Cavett, these 3-4” slicers are juicy with a well-balanced flavor.
- Red Robin—a lovely dwarf cherry that can even be grown indoors on a sunny windowsill.
- Superbush—bred specifically for small spaces, this tomato still has a big, old-fashioned tomato flavor.
Still having a hard time deciding? So many possibilities! Well, we'll have lots of knowledgeable Master Gardeners all-day at all of our Great Tomato Plant Sales to help you with your selections. We want to make sure that you take home tomato plants that will thrive in your garden and will also meet your personal preferences. There's literally something for everyone. For your convenience, we also have online shopping lists for you to mark up and bring to the Sale.
Visit our website at http://ccmg.ucanr.edu/EdibleGardening/GreatTomatoPlantSale/.
See you at the Sale!
