by Donna Woodward

Last month I reported on our ongoing trial with growing tomatoes in containers.  To recap briefly, we are growing three different tomato varieties in containers.  Our goal is to learn about best practices for growing tomatoes in containers and to see if these three varieties are suitable for this method. The three varieties we chose all claim to be suitable, but we don't always trust the seed catalogs!  They are Renee's Better Bush (a round slicing tomato), Inca Jewel (a paste or Roma type), and Prairie Fire (a grape tomato).

Our Field Test committee met recently to check in on our progress.  Most of us reported our tomatoes growing quickly and in good health.  So far, the weather hasn't been too hot, which has been a boon.  We discussed strategies for hot summer weather, which is almost certain to hit us eventually.  Most of us planted our tomatoes in large black plastic pots.  This material attracts heat and doesn't have any insulation, so it will be hard on tomato roots confined in such a space. Several ideas were offered on ways to shield the pots from the direct sun.  Painting them white should help, since white reflects heat, as opposed to black, which absorbs heat.  Pots can be wrapped in insulating materials.  They can be placed inside a slightly larger box, which will absorb heat and provide shade.  You can place potted plants or other obstacles around them.  In hot weather some shade can be helpful.

Your watering schedule should provide consistent moisture for the roots.  Watering from the bottom is recommended, providing you have a large enough tray to put under the pot.  If this is not possible, water from the top deeply enough that the water can drain out of the bottom.  Some drooping of leaves in mid-afternoon is not cause for alarm.  Water in the early morning or evening. Soil should be kept moist but not wet.  One useful tool is a probe for detecting moisture levels.  These are inexpensive and give you some peace of mind if you're unsure about when to water. 

If your plants are getting tall, it's time to stake them.  You can put a tomato cage over the plant with the feet buried inside the pot.  If you place the plant against a wall or pole, you can tie the stake to that to add stability.  Any structure that will stay firmly in place and can contain the growing stems will work.  The corner of a gazebo is a great place for a plant.  It's best to get the stakes in place early so you can gently tuck the new growth inside the horizontal constraints and keep them growing upward.  Otherwise, they will grow sideways and be vulnerable to breakage.  Prairie Fire is the one test plant that is semi-determinate, meaning a vining type that will continue to grow taller, so it is most in need of support.  The other two are supposed to grow to about 3 feet, but they may need support as well.  Better to be safe and provide support than to have the stems fall over and break off. 

Whether and when to fertilize depends on your planting materials.  An all-purpose planting mix will provide all the fertilizer you need at first, but as the plant grows and consumes the available nutrients you will have to add some food.   A plant in the ground can send its roots down and out to search for more nutrients but a plant in a pot is limited to what you can provide.  The potting soil bag probably specified some guidelines for when and how much to fertilize.  When you do fertilize, choose an all-purpose balanced fertilizer.  Monitor your plants carefully and be alert to changes in color or vigor.

Napa Master Gardeners are available to answer garden questions by email: mastergardeners@countyofnapa.org. or phone at 707-253-4143.  Volunteers will get back to you after they research answers to your questions.

Visit our website: napamg.ucanr.edu to find answers to all of your horticultural questions.

Photo: Donna Woodward

 

 

by Cynthia Kerson

The UC Master Gardeners of Napa County have started spring and summer home garden tours. It's a chance for members to tour each other's gardens, share ideas and visit with each other. I'm not sure if everyone else on the May 26^th garden tours were as dizzy as I was with all the Latin names being thrown around. I can barely remember common names, so to listen to the MG homeowners rattle them off as if they are family members was quite impressive. Both gardens we toured were beautifully developed and provided tons of beauty and food for our outside roommates, and were thoughtfully water-wise. They were filled with cuttings and gifts from other MGs over the years and each gardener remembered and told the story of each. One such flower (pictured) is a poppy, appropriately blooming for the Memorial Day weekend that the owner had received from a friend who had propagated seeds gathered from the plantings along a street in Napa.

One of our garden owners waters twice a week for 20 minutes from her well-designed drip system. She shared that one of her plants wasn't “performing” as well as she had hoped and bent down to apologize to it while patting it.

The second garden we toured has two water features that water the surrounding plants and provide drink and fun for some outside neighbors as well. She also has a functional drip water system and waters depending on the hydrozone, from twice a week for vegetable beds, to twice a year using a rain garden for native plants. It was interesting to note from the walkway to her home the influence she must have on her neighbors' gardens.

She has been experimenting with perennializing vegetables over the past couple of years by cutting them to the ground and seeing what they do. Pictured is a Swiss Chard and she reports that the leaves are still delicious, but she will have to get her garden saw out to cut it back this year as the stem has grown so large. 

The properties we toured are quite different from one another – one is sprawling in the Coombsville area among massive wineries and the other is in central Napa proper.  Both gardens speak the same language, though – support nature, be conscious about water, and develop and live in beauty.

Napa Master Gardeners are available to answer garden questions by email: mastergardeners@countyofnapa.org. or phone at 707-253-4143.  Volunteers will get back to you after they research answers to your questions.

Visit our website: napamg.ucanr.edu to find answers to all of your horticultural questions.

Photo credits: Cynthia Kerson

Information links:

UC IPM  Poppies ; UC ANR irrigation in the home garden ; UC ANR  perennial vegetables

by Saira Bates

A few years ago, I found a couple of plants growing at the base of the bird house in my garden. At first, I thought they were weeds. I was tempted to pull them out, but I was also curious to see if there would be any flowers on this rapidly growing plant. I decided to let them grow. In a couple of weeks, I came to recognize that they were hollyhocks. Since I hadn't planted them, I suspected they were a gift from the birds in exchange for their lodging.

Two years ago, I collected some of the seeds and planted them in a better spot in my garden. Last year they came up but no flowers. This year, they seem to be growing well and have buds that should be opening soon. However, I noticed small holes in most of the leaves. Upon closer inspection, I could see several tiny black bugs with what appeared to be elongated snouts. I did a quick search on the UCIPM website and was able to identify them as weevils (family Curculionidae). They are a common pest with various species that use different types of plants as hosts. Adults like to eat leaves and buds but the larvae of some species feed on roots of the plants. As per UCIPM, the best way to deal with weevils is to hand pick them. I armed myself with ½ cup of soapy water, hand-picked the weevils and dropped them into the soapy water. If you are little squeamish about picking up bugs, try simply holding the cup close to the plant and flicking the buds, stems, and leaves of the plant, which will dislodge the weevils into the soapy water. I have been checking my hollyhocks daily and, to date, have not seen any weevils. You can learn more about weevils here: https://ipm.ucanr.edu/PMG/GARDEN/FLOWERS/INVERT/weevil.html

I'm so happy that hollyhocks showed up in my garden. I've learned that hollyhocks don't normally produce flowers during the first year, can grow to be 6 feet tall and are generous seed producers, along with how to control a common pest, the weevil, using an environmentally friendly method.

Napa Master Gardeners are available to answer garden questions by email: mastergardeners@countyofnapa.org. or phone at 707-253-4143.  Volunteers will get back to you after they research answers to your questions.

Visit our website: napamg.ucanr.edu to find answers to all of your horticultural questions.

Photo credits: Saira Bates

Information links: UCMG Riverside County  Hollyhock info

by Donna Woodward

The Tomatoes-in-Containers Trial
We gardeners who have space to grow plants are fortunate. Many people would love to grow some vegetables, such as tomatoes, but have no garden space. We Napa MGs in the Field Test Committee felt we should do something to help these people. We decided to try a field (patio?) test for tomatoes. There are several types of tomatoes bred for growth in containers. We picked three to grow on our patios, decks, or anywhere other than in the ground or a raised bed. Most of us had never tried this, so it promised to be a novel experience.

Super Bush

Then we had an even better idea: We coordinated our trial with the annual tomato sale, which was held on April 15 th, and invited the public to participate. We had a booth at the tomato sale where people signed up, took a data sheet, and agreed to keep notes while growing any of the designated varieties.

We will poll them later about their experiences and add this data to our own.
We did some research on various tomatoes touted as suitable for growing in containers. One factor is whether the tomato is determinate or indeterminate. The former is a bush type that grows to a certain height, so this would probably work better in a limited space. We learned that there are dwarf varieties that are bred specifically for growing in pots. There are even micro-dwarf types that can be grown on a windowsill. Some of these were available at the sale, but we didn't want to experiment with a novelty. We decided to try three normal-sized plants that are reputed to do well in containers.

We picked one general-purpose round slicing tomato, one cherry/grape tomato, and one paste type. For the slicer we picked Super Bush, a determinate variety that is supposed to grow to about 3' in height. We picked a grape tomato called Prairie Fire, which is a small oblong tomato that had rave reviews from some who had grown it before. This one is indeterminate, but we cautioned everyone to provide good staking.

The last choice, Inca Jewel, is a paste type, also called plum or Roma. This is the kind of tomato used for making sauces because its flesh is thicker and meatier than other types. We were stymied by the prospect of getting so many empty containers without spending an exorbitant amount of money. We were lucky to find a tree farm that was willing to donate some large plastic containers. We were all responsible for purchasing our own soil. No supplies were offered to the public.
At the tomato sale anyone who purchased one or more of the three varieties in the trial was invited to participate. We were delighted to get 42 people to join our trial! We'll post updates over the coming months as the growing season progresses.

Napa Master Gardeners are available to answer garden questions by email: mastergardeners@countyofnapa.org. or phone at 707-253-4143.  Volunteers will get back to you after they research answers to your questions.

Visit our website: napamg.ucanr.edu to find answers to all of your horticultural questions.

Photo credits: Donna Woodward, Reneés Garden (Super Bush) Prairie Fire and Inca Jewel by previous permission.