Days to harvest

Another thing to look for is the “days to harvest” (DTH) or “days to maturity” (DTM).  These are approximations of how long it takes to get ripe fruit from the time  you plant transplants in your garden.  Typically, the DTH runs from around 65 days for early tomatoes and up to 85 days for late varieties.

Be aware that DTH is an approximation.  Yes, a 70 DTH variety may take that long if weather conditions are perfect, with temperatures of 75F to 80F days and 65F at night.  Obviously, we don’t have these ideal  temperatures early in most seasons in upstate New York.  Under our conditions, that 70 day variety may take closer to 80 days.  Days to harvest is best used to compare varieties and not as a firm predictor of your first harvest.

Hybrids and heirlooms

The term “hybrid” is often used in describing tomatoes.  A hybrid refers to a specific cross a plant breeder made to come up with an improved variety.  Perhaps the breeder crosses a very disease-resistant tomato with poor quality fruit with a disease-susceptible variety with great fruit to produce hybrid seeds that will produce plants with the best traits of each parent.  Hybrid tomato breeding has been going on for more than 100 years.

A note about tomatoes and genetically engineered varieties.  There are no tomato varieties available in this country that have been genetically engineered.  None.  Hybrids available today are the result of painstaking crosses made by tomato breeders, using only tomato genetic material. 

Another term you may see on a label is “heirloom.”  This refers to a non-hybrid or “open-pollinated” (OP) variety that has been selected and passed down from one generation to the next. Good examples of these include ’Brandywine’, ’Cherokee Purple’ and Mortgage Lifter’.  They tend to produce larger fruit. But there are also smaller heirlooms, such as ’Mexico Midget’.

People often assume that an heirloom variety is always disease-resistant and high yielding.  That is not always the case.  Some are like disease magnets and are the first ones to succumb to plant pathogens.  Typically, heirlooms taste great.  ‘Brandywine’ usually comes out on top for flavor.  But ‘Brandywine’ varieties crack easy and have poor disease resistance.

The best of both worlds

Cornell plant breeder, Martha Mutschler-Chu created a new hybrid using ‘Brandywine’ as one of the parents.  The new ’Brandywise’ variety provides a great tasting fruit, high disease resistance (resistant to late blight and Septoria and tolerant of early blight), and less fruit cracking.  It’s worth trying if you can find plants.  Seeds are available from Fruition Seeds.

One of our Cornell plant breeders, Phil Griffiths, similarly tapped into the good-tasting genetics of heirloom varieties to develop the Galaxy Suite of six grape tomato varieties in a veritable rainbow of colors.

There are lots of diseases that affect tomatoes.  My colleague Dr. Christine Smart, a plant pathologist at Cornell, says the most effective thing a gardener can do is choose hybrids with the best disease resistance.  If a variety is resistant, you no longer need to worry about that disease.

There is one disease where a specific resistance may be referred to on the label. That’s late blight.  This is a disease caused by a fungus-like pathogen, the same disease that caused the Irish Potato Famine in the 19th century.  It can devastate tomatoes (and potatoes) in a few days and its spores can fly through the air and infect plants miles away.  Although devastating, we don’t see it here every year and it’s virulence depends on three things.

First, it has to be present in the environment.  Second, weather conditions need to be optimum for spread.  Mild, cloudy weather with high humidity and showers are ideal.  Sunny, dry weather prevents spread.  And finally, you need to have a susceptible plant. 

Up until about 10 years ago, we had no late-blight-resistant tomato varieties. But that has now changed.   ‘Brandywise’ is a good example of this resistance.  And typically, if a variety has resistance to late blight it will also show resistance to other diseases like early blight or Septoria.

There are a few more terms you may see as you research which tomatoes to grow.  A beefsteak type will be large-fruited (8 to 12 ounces or larger) and great for slicing. Cherry and grape types are small, usually less than an inch in diameter.  Paste tomatoes are used for making sauce.  They typically have few seeds and less liquid. Dwarf or compact varieties are your best choices for pots or containers.

The majority of tomatoes are red, of course. But there are lots of other colors available.  Yellow, orange, purple and even some that are completely green when ripe. Most tomatoes are roundish but there are some that are more oblong, or pear shaped.

It might be a good idea to bring your smartphone with you so you can look up variety names as you shop.  Two websites in particular can help you learn more about different varieties: Rutgers’ Tomato Varieties website and Cornell’s Vegetable Varieties for Gardeners, a great site where you can see recommendations for all garden vegetables. 

In the garden this week.

Seems like a few weeks ago we were concerned about it being too dry.  Certainly not the case now.  If your soil is dry enough to work, now is a good time to plant all the “cole” crops (cabbage, broccoli, etc.), leafy greens, potatoes, carrots, beets, onions, and radish.  Now’s a good time to clean/sterilize your used tomato stakes and cages.  Bacterial diseases can easily overwinter and infest this year’s crop.  Clean off any dirt and debris and soak for at least 10 minutes with a bleach solution (1 part bleach and 9 parts water), remove, and let air dry. 

Common tomato varieties available locally in 2021

The following table includes brief descriptions of varieties available locally this spring.  Thanks to Master Gardener Francine Stayter for visiting several garden centers and providing the list.