Start your tomato plants off right by spacing them properly. It’s the first step to encouraging healthy plant growth and large harvests. Overcrowding plants limits air flow which can increase the occurrence of diseases, but it also impacts light exposure. Planting tomatoes too far apart means you’re not maximizing the growing space. In this article you’ll learn that tomato spacing depends on two factors; what types of tomatoes you’re growing and how you plan on supporting the plants. Once you have those key pieces of information, it’s easy to figure out how far apart to plant tomatoes. Keep reading for all the details.
How far apart to plant tomatoes: Why tomato spacing is important
There are four main reasons to aim for well-spaced tomato plants:
- Disease prevention. Tomato plants are susceptible to many diseases and if spaced too closely, insufficient air circulation can elevate the risk of disease.
- Adequate light. Heat-loving tomato plants need plenty of sunlight for healthy growth. If you crowd seedlings, the plants will cast shade on their neighbours as they grow.
- Production. I like to use up all my growing space leaving little open soil for weeds to grow. Spacing tomatoes too far apart means that you’re leaving space for weed growth, losing valuable growing space, and reducing your overall potential harvest.
- Less competition. As noted above, air flow is decreased when plants are crowded, but it also means they’re competing for water and nutrients.
Types of tomatoes
As you flip through seed catalogs and ready seed packets you’ll notice descriptions like determinate, indeterminate, bush, and vining. It’s important to know mature plant size when you’re trying to determine how far apart to plant tomatoes. Below you’ll find more information on the two main types of tomatoes.
Determinate – Determinate tomato plants, also called bush tomatoes, form compact plants that grow about three feet tall, although some larger varieties can grow up to four feet. Because the fruits of determinate tomatoes ripen around the same time, they’re often grown by gardeners who like to preserve their harvest or make big batches of sauce or salsa. Determinate tomatoes are often left unsupported, but I prefer to keep them upright with sturdy tomato cages. This keeps the foliage off the ground, reducing the risk of soil-borne diseases. It also ensures that sunlight reaches all parts of the plant to support photosynthesis.
Indeterminate – Unlike determinate tomato plants which grow to a certain size and stop, indeterminate varieties can grow six to eight feet tall. They only stop growing when an autumn frost finally kills the plants. Also called vining tomatoes, indeterminate varieties yield their harvest over a long period of time and are best grown on sturdy supports like tall wire cages, stakes, or a trellis system. I also like to prune my vining tomato plants to direct growth and boost fruit production.
How far apart to plant tomatoes
How far apart to plant tomatoes is dependent on the types of tomatoes grown – determinate or indeterminate – and the types of supports used. Trellised plants in sturdy tomato cages or supports can tolerate a closer planting than those left to sprawl on the ground. Of course, there are other benefits to trellising your tomato plants. They’ll be less likely to suffer soil-borne diseases like early blight and it makes it more difficult for pests, like slugs, to climb up the plants.
Determinate tomatoes – Space dwarf determinate tomatoes, which only grow 12 to 18 inches tall one to two feet apart. Full-sized determinate tomatoes should be planted two feet apart. If growing micro tomatoes, which are ultra compact varieties, space them 8 to 10 inches apart.
Indeterminate tomatoes – This is where supporting your plants makes a big difference with spacing. I plant staked indeterminate tomato plants 18 to 24 inches apart. They are pruned regularly during the growing season to control growth and encourage good air circulation. You can also use tomato ladders or extra tall tomato trellises to keep indeterminate plants off the ground. Again, space them 18 to 24 inches apart. If you don’t want to stake vining tomatoes you can let them to sprawl on the ground, but be award that they can create quite a large mound of foliage. In this case, space the plants about four feet apart.
How far apart to space the rows?
When growing in gardens or raised beds, leave four feet between rows to permit good air flow and, in the case of in-ground gardens, to give you space to work around the plants.
Keep on top of pruning
Now that you’ve got your tomatoes properly spaced, don’t neglect pruning! Determinate tomatoes don’t need to be pruned, but staked indeterminate tomatoes need regular pinching to remove suckers which promotes healthy, productive plants. It’s not difficult to prune tomato plants, but it should be done every 7 to 10 days. Suckers are vegetative shoots that develop in the crotch between the main stem and a branch. Suckers do produce flowers and fruits and while leaving suckers can mean more tomatoes, the overall fruit size will be decreased. And of course, the plants become a tangle of foliage with little airflow.
In early summer, I let two to three suckers develop, but pinch the rest every 7 to 10 days. When the suckers are 2 to 3 inches long they’re easy to remove with your fingers. If you let them grow larger, you may need a pair of pruners to cleanly remove suckers.
Learning how far apart to plant tomatoes isn’t difficult, and it’s so important for the health and production of your plants. For further reading on growing tomatoes, be sure to check out the award-winning book, Epic Tomatoes by Craig LeHoullier.
For more on growing tomatoes, check out these related posts:
- Tomato growing secrets for high yields and healthy plants
- How to grow tomatoes from seed
- 5 tips for growing tomatoes in raised beds
- 4 ways to overwinter tomatoes
- Should you grow grafted tomatoes?
- Companion plants for tomatoes
Have you been wondering how far apart to plant tomatoes? Any tips to add?