You Can Grow Tomatoes in a Shady or Foggy Garden

A Shady or Foggy Garden? You Can Grow Tomatoes!

A Shady or Foggy Garden? – You Can Grow Tomatoes!

Well, it’s that time of year when we are happily preparing our garden beds and pots for our vegetable planting! We are either gathering our purchased vegetable seedlings or transplanting the seedlings we have grown – or some of both. And among those are tomatoes - unless perhaps you are one of the many living in the cool coastal or wooded areas of Alameda County. If you fit in that category, you may be thinking “There’s no way I can grow tomatoes!” or “Tomatoes have never worked in my yard!” If that sounds like you, there is likely more hope than you think, and this article is for you!

Now it may be true that if you live in a very heavily wooded area, with no sunny corner in any part of your yard or patio or porch, you may not be able to grow sun-loving vegetables like tomatoes. But if you have sun anywhere outside your home, even if for only part of the day, please read on! There are tomato varieties that have been developed just for your situation.

The key to growing tomatoes in cooler climates is to grow varieties that have a relatively short number of days to maturity or that produce a harvest in cooler temperatures. Fortunately, there are now a number of these tomato varieties, and with some experimentation, you will likely find one that works for you. For best results, plant your tomatoes in the area of your yard that received the most hours of sun. This may be an area in your yard or even in containers on your patio.

Days to Maturity

Days to maturity (DTM) means the number of days from planting a seed to when the seedling grows into a mature plant and begins to produce a harvest. The range for “days to maturity” for tomatoes is about 55 to 100 days, and of course, depends upon the variety grown. For best results in cooler climates, try tomato varieties with 55-75 days to maturity. Although there are exceptions, many of these varieties have been found to do best in cooler locations. In addition, tomatoes often take longer to mature in cooler climates. Using varieties with shorter warm weather maturities will give your harvest a longer time to ripen in your cooler climate.

Varieties that Produce in Cooler Climates

University of California researchers have evaluated several tomato varieties for growth and production in three different climatic zones in our state, designated as A, B, and C. They have recommended varieties for use in the zones in which they proved successful. (Many other popular tomato varieties have yet to be evaluated in this way).

The coolest of these zones is “Zone C”. This Zone includes the central and northern coastal areas, the cool coastal valleys from Santa Maria north to the Oregon border, the San Francisco Peninsula, and areas with direct exposure to San Francisco Bay, the northern coastal foothills, and other areas with cool to moderate summers and evening temperatures frequently in the 45° to 55° F range. Alameda County cities located in Zone C include Alameda, Oakland, and Berkeley. 

Listed below are some of the tomato varieties the researchers found did well in Zone C, sorted by three types: small cherry tomatoes, standard size, and container tomatoes. Of course, your own results will depend upon the microclimate in your own neighborhood, and even within your own yard. Some tomato varieties produce well in large pots, so if that is your warmest spot try the container varieties below.

Cherry Tomatoes

Sweet 100: Gardener's Delight: Sweet Chelsea

Images and information courtesy of San Mateo/San Francisco Master Gardener at https://www.notion.so/Tomatoes-344ebbc109e64203b233d7f7eae2acb0

Standard Size Tomatoes

Early Girl: Stupice: Early Wonder

Images and text boxes reprinted from San Mateo/San Francisco Master Gardener 

Container Tomatoes

Image courtesy of Mississippi State Extension 

Determinate vs Indeterminate Tomatoes

You’ll notice that each of the varieties above states whether they are “determinate” or “indeterminate”. Tomatoes are described as determinate or indeterminate based on the plant’s growth habit.

Determinate, or “bush,” tomato plants have a somewhat bushy appearance, grow to a given size, (about 3 to 5 feet), bear most of their fruit within about 4 to 6 weeks, and then decline in vigor. Most early-ripening and canning tomato varieties are of the determinate type. All the above-recommended container tomatoes are determinate.

Indeterminate varieties produce vines that continue to grow and set fruit all summer until they die from cold weather or disease. Many typical standard-sized tomatoes for the home garden are indeterminate varieties. The cherry and standard tomatoes recommended above for cool weather growing are all indeterminate.

Left to grow without support, indeterminate plants tend to sprawl on the ground, leaving the fruit susceptible to rot where it comes in contact with the soil. So support these plants with sturdy trellises, cages, or stakes.

Growing Your Tomato Plants

Try two or more varieties; experimentation is fun and the best way to find the tomato that grows best in your yard! Once you plant them, whether from seed or seedling transplants, growing tomatoes is fairly easy. The links below have much more information on the care, feeding, watering and pest management for your tomatoes:

https://ucanr.edu/repository/fileaccess.cfm?article=54222&p=%20ZKXKHX

http://ipm.ucanr.edu/home-and-landscape/tomato/cultural-tips/

http://ipm.ucanr.edu/home-and-landscape/tomato/index.html

References

https://ucanr.edu/repository/fileaccess.cfm?article=54222&p=%20ZKXKHX

https://www.notion.so/Tomatoes-344ebbc109e64203b233d7f7eae2acb0
From the San Mateo/San Francisco Master Gardener webpages

http://extension.msstate.edu/news/southern-gardening/2008/interest-patio-gardens-spreads

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