As with other crops, each tomato variety is either a variety bred in modern times (often a hybrid, the offspring of two very different varieties) or a traditional, open-pollinated variety unchanged since WW2 (often called an “heirloom”).
Within each of these two large groups, there are several importantly different types of tomatoes:
1) slicers (large, fairly round tomatoes, often red, with a high water content, for use in sandwiches, etc.),
2) Roma, plum, or paste tomatoes (smaller, oval, with a lower water content, usefulfor drying or making tomato paste), and
3) small, bite-sized tomatoes of varied colors, shapes, and flavors, including yellow pear tomatoes and red cherry or grape tomatoes (good for eating whole, like grapes).
It’s good to know which of these you want before you plant!
Every tomato variety is also either determinate or indeterminate.
Determinate tomato plants grow to a certain size (about 1.2-1.5 m) and then stop growing.
All of their fruit becomes ripe in a short time window, usually about 2 weeks, and then the plants begin to die, producing no additional fruit.
Indeterminate tomato plants, by contrast, grow from the time you plant them until they are killed by frost, and can reach heights of 2-3 m if they are supported.
They produce and ripen new fruit steadily until frost.
Both indeterminate and determinate tomatoes need to be caged or staked, even so-called “dwarf” varieties.
Most (but not all) modern hybrid varieties are determinate, including most large red slicing tomatoes and most Roma or “paste” tomatoes.
Most (but not all) traditional or “heirloom” varieties are indeterminate.
Most (but not all) cherry tomatoes are indeterminate and can grow very, very tall.
Before you plant a tomato, find out it if it is indeterminate or determinate!
Many people are disappointed when their determinate tomato plants die in May or early June, even though it’s completely natural.
Information about tomato planting dates
Tomatoes have no frost tolerance and must be protected carefully if they are planted while there is still risk of frost.
It’s safest to wait until all risk of frost has passed before planting tomatoes.
Many growers plant a first planting of determinate tomatoes as early as possible, then put in a second planting of indeterminate tomatoes 4 to 6 weeks later.
The determinate tomatoes will yield a large amount of fruit quickly (good for summer canning, freezing, and eating), after which they stop producing and can be removed to make space for other crops. The indeterminate tomatoes
start producing soon after and keep going until frost.