Choosing Tomato Varieties

By Kim Wilson, UC Master Gardener

“Home grown tomatoes, home grown tomatoes What would life be like without homegrown tomatoes Only two things that money can't buy That's true love and home-grown tomatoes.” (from a song written by Guy Clark)

Details to consider when choosing the best tomato for your garden:

Determinate or Indeterminate

Space and harvesting considerations require understanding of the growth characteristics of the tomato. There are two main groups of tomatoes: determinate and indeterminate.

• Determinate tomatoes or bush tomatoes are compact and grow to 3 to 5 feet tall. Most require some staking or small 3 foot tall cages, although others can be quite compact.  Determinate type tomatoes should be planted 18 to 24 inches apart and are best suited for gardens with space limitations.

Determinate Tomatoes grow to a set height, flower and set fruit over a short period of time. The tomatoes ripen over a 4-6 week period, after which the plant declines.  Determinate tomatoes are ideal for gardens with short tomato growing seasons due to either too cool or too hot temperatures. They are also ideal for gardeners with the goal of preserving the fruit.

• Indeterminate tomatoes are vines which will continue to grow throughout the growing season and can reach 8 to 12 feet in height. These tomatoes need strong 6 foot tall supports: cages reinforced with stakes, stakes or trellis system.  They should be planted 24 to 36 inches apart to allow for growth and adequate air circulation.

Indeterminate tomato vines will continue to grow, flower and set fruit until the plant is killed by frost or disease.  These plants tend to take longer from planting to ripe tomatoes so are not optimal for short season gardens or cool climates.  They are ideal for gardeners who value having ripe tomatoes for fresh eating over a long season.

Climate

It is important to consider your microclimate when choosing tomato varieties for your garden. Tomatoes should be planted after the danger of frost has passed and the soil temperature is above 50°F. Planting too early can result in frost damage or slowed growth of the plant. Tomatoes thrive in warm climates and require 6 to 8 hours of sun per day. The term fruit set refers to a tomato flower that actually produces a fruit. If fruit set is low, you will see flowers but few resulting fruit.  Fruit set can be disrupted by low light, smog, or several days of temperatures below 55°F or above 90°F. 

Days to Maturity

The days to maturity is listed on the seed packet and refers to the number of days from planting your tomato seedlings in the garden to the date of the first mature fruit.  Days to maturity for tomatoes ranges from less than 50 days to more than 90 days, depending on the cultivar.  Large tomatoes and heirloom tomatoes take longer to fruit.  If your warm growing season is short, as in coastal regions, then short season varieties with fewer days to maturity are recommended.

Hybrid vs Heirloom

Hybrid tomatoes are bred from genetically different parent plants to produce specific characteristics relating to color, days to maturity, weather tolerance, and disease resistance.  These tomatoes tend to be short season and disease resistant varieties.  Seeds of hybrid tomatoes cannot be saved and propagated as the resulting tomato plant will not be the same as the parent.
	Heirloom tomatoes are open pollinated varieties which have been passed down at least 50 years through families or ethnic groups or were commercially available before 1940.  Generally, they tend to be longer season tomatoes that can be less productive and not as disease resistant but are valued for their unique tastes and wide variety of colors and shapes.   Heirloom seeds can be saved for planting as the seeds remain true to the parent plant.

Open Pollinated tomatoes may or may not be heirloom tomatoes, but their seeds can be saved and planted as long as care has been taken to prevent cross pollination with other tomato varieties.

Disease Resistance

If tomato diseases have been a problem in your garden, consider planting disease resistant or tolerant plants.

• Fusarium wilt and Verticillium wilt are both soilborne fungal diseases which cause wilting and yellowing with eventual death of the plant. Since the fungus survives in the soil for up to 6 years, crop rotation can help.   However, purchasing disease resistant hybrid tomatoes is recommended.
• Tomato Spotted Wilt Virus is not soil borne but transmitted via insect, specifically thrips from nearby weedy fields. The result is bronzing of leaves, stunted plant growth and abnormally colored fruits with rings, spots and bumps. There is no treatment. Resistant tomato varieties are available.
• Look for resistant seeds identified by abbreviations on the tomato label: (V) verticillium wilt, (F or FF) fusarium wilt, (N) nematodes, (T) tobacco mosaic virus, (TSWV) tomato spotted wilt virus, (A) Alternaria.

References

Finnigan, Monica. 2016. "Choosing the Right Tomato For YOU!". ANR Blogs. Choosing the Right Tomato for YOU! - Napa Master Gardener Column - ANR Blogs

Gao, Gary, Brad Bergefurd, and Bob Precheur.  "Growing Tomatoes In The Home Garden, Ohioline OSU.EDU. Growing Tomatoes in the Home Garden | Ohioline

Pittenger, Dennis, Nancy Garrison, Pamela Giesel, and Carolyn Unruh. 2016. Growing Tomatoes In The Home Garden. UC ANR Publication 8159. Growing Tomatoes in the Home Garden