One of the most important steps to growing healthy tomato plants is proper spacing. Tomatoes like to have a good amount of space between each plant for good aeration.
In this article, I’ll discuss proper tomato plant spacing and all that goes along with it. I’ll also cover the important reasons that I space the plants how I do, and how it can differ if you are growing in the ground vs in containers.
In short, tomatoes should be planted 24-36 inches away from each other, from one stem to another. The main reason tomatoes need so much space is for good aeration, which helps prevent infection, though there are other benefits, too.
Tomato Plant Spacing Guidelines
Tomatoes are fast-growing plants that tend to take over the garden if left unchecked. It is a common misconception that smaller tomato varieties (ie. grape, cherry, etc.) grow on smaller plants. This is false!
In fact, unless the variety is specifically bred to be a ‘dwarf’ plant, most tomato plants are very large when fully grown. Indeterminate varieties can be even larger, as they will continue to grow throughout the season until the weather becomes too cold.
Note: Read up on the specific tomato varieties you are growing. Some of the determinate plant varieties are specifically bred to remain small, so these could likely be spaced closer together.
In addition to being large, tomato plants are highly susceptible to disease, especially blight. Blight is a fungal disease that is extremely abundant and spreads via insects and wind-borne spores. It also requires moisture to infect a plant.
So, to help reduce the likelihood of your tomato plants developing blight (and other diseases), wide plant spacing is highly recommended.
In-Ground Tomato Plant Spacing
When your tomatoes are planted in an open garden bed or a raised bed, spacing should be at least 24″, and up to 36″ if you have the space. This allows for the natural wind to breeze through your tomato garden with ease.
This is a classic case of “less is more,” as having more tomato plants won’t do you any good if they all end up dying from blight! There are some other important measures to take when planting your tomatoes in a garden bed that are covered below (see here).
Container Tomato Plant Spacing
When planting multiple tomato plants in containers, the plants can, of course, be moved at will. However, if you plan to keep them stationary, they can be kept a bit closer to one another.
The reason potted tomatoes can be spaced closer is that planting in a container naturally raises the plants off the ground. If you follow my guide to the ideal container size for tomatoes, your plants will be lifted about 12″/30cm off the ground by the container itself.
This higher position helps to increase airflow around the base of the plants naturally, so I generally keep potted tomatoes closer without running into issues.
Generally speaking, potted tomato plants can be spaced about 18″/46cm from one another, stem to stem. This spacing, in addition to bottom pruning and mulching, is perfect for container plants.
When you transplant your tomato plants into the garden with a 36″ spacing, you may feel silly. The plants are still fairly small and the spacing will feel way too wide.
However, once the plants are full-sized, you’ll be glad you stuck to the plan! With enough of a growing season, tomato plants can grow to be 5′ or (much) taller.
Having a wide tomato plant spacing also help when it comes time to harvest your tomatoes. Additional space between plants makes it easier to access your ripe tomatoes when the time comes.
Other Important Spacing Tips
In addition to the physical distance between your tomato plants, you should take a few other steps to help keep the plants healthy. Every day when I check in on my tomato plants, I am thinking about whether they have enough room to breathe.
- Bottom prune for aeration. If you are growing tomatoes, a nice pair of pruning shears will become your best friend. there are several types of pruning methods, but one of the most universal across all varieties is bottom pruning. Keep the lowest branches of your plants trimmed back so that there is about 12″ of space between the ground and the first branches. This allows currents of air to flow easily below the plants, helping to evaporate excess moisture from the leaves.
- Mulch around base of plants. Mulching helps in multiple ways, but one role is to avoid splashing when it rains. Heavy rainfall will kick up a lot of dirt, potentially inviting soil-borne spores to infect your tomatoes. Mulch dampens the rain and blocks this potentially harmful splashing. I like to use straw or grass clippings as a cheap and effective mulch.
- Prune unwieldy leaf stems. Back to pruning! In addition to bottom pruning, I like to occasionally remove a few excess leaf branches throughout the entire plants. Like bottom pruning, this allows more airflow throughout the entire plant, allowing the leaves to dry off if they become wet (from morning dew or rainfall).
Keeping your tomato plants well-manicured throughout the season goes hand-in-hand with proper plant spacing. These practices will help your plants stay sturdy and attractive, as well as free from disease.
What To Plant Near Tomatoes
With all of that open space between your tomatoes, you may wonder if it can be used to anything else. Perhaps some small plants can fill the garden space to avoid wasted space.
Yes! I recommend using the 24-36″ of space for one or two small beneficial companion plants. In general, any herb or small shrub can work, just avoid anything that grows to be too tall or bushy.
- Basil. Of course! Basil is an amazing tomato plant companion, perfect for filling the plant spacing between your tomatoes. Just be sure to harvest your basil regularly to prevent the plants from becoming too large or from bolting.
- Chives. Another easy-to-grow plant that can easily fill in the space are chives. The plants remain relatively small, perfect for planting between tomatoes.
- Garlic. I love to throw garlic all around my garden, wherever it will fit. It takes up minimal space, and can be planted very close together. Also, tomatoes and garlic work pretty well together in the kitchen!
There are many other great tomato plant companions, but these are some of the best for planting between your large tomatoes. Other plants, like squash, beans and sage are great to plant nearby, but are too large to fit between the tomato plants.
I hope this article helps you determine the right tomato plant spacing for your garden this year! Remember, it is better to have fewer healthy plants than too many unhealthy ones. Happy growing!