Grow them too close together, sunlight gets blocked, humidity increases and the next thing you know, you’re trying to figure out why there’s so many white spots on tomato leaves – powdery mildew!
In family-sized vegetable gardens, a respectable number of tomato plants is one to four plants per person. The more tomatoes your family goes through, the more space you’re going to need.
When your garden’s compact, that could be a problem!
How Far Apart to Plant Tomatoes?
Dwarf tomato plants need at least 6” space between plants. These are determinate varieties meaning they stop growing about 4’ in height. Indeterminate tomato plants don’t stop growing until the first frost so those need more space, typically around 18” minimum. If you’re growing in rows, you need at least 2-feet between them. For growing heirloom tomato plants that you want to save the seeds for next year, 10-feet of spacing should be between the plants to lower cross-pollination opportunities.
Determinate Vs Indeterminate Tomato Plants: What’s the difference?
A determinate plant stops growing at some point. An indeterminate tomato plant continues growing until it can’t. That’s usually at first frost.
- Indeterminate tomatoes are better to grow on trellises and stakes because you’re in control of their height.
- Determinate tomato plants tend to reach heights of up to 6’, unless it’s dwarf tomatoes, which tend to peak at 4’ tall.
The taller your plant grows, the more space it’s going to need.
Recommendations for determinate varieties are minimum of 18”, but if you plan on growing a towering vine that’s taller than 6’, consider increasing space between plants to 24” or more.
What Distance Should be Between Rows of Tomato Plants?
For growing rows of tomato plants, you need space to tend to your plants without disturbing the soil too much. You also don’t want your plants competing for soil nutrients.
To avoid competition between crops, and give yourself sufficient space to tend to your plants, aim for no less than 2’ spacing between rows.
For tomato plants being grown without supports, such as cages, trellises, or stakes to support vertical growth, spacing should be increased to 3’ to 4’.
Less space is only recommended if you’re promoting vertical growth.
Dwarf tomato plants need the same 3’ to 4’ spacing between rows, too.
Spacing Requirements for Container Grown Tomato plants
You don’t need a huge garden to grow fresh tomatoes. Containers do just fine on sunny patios, roof terraces, balconies, and completely hardscaped gardens. They still need space though, both in the container and around them.
The size of container to grow tomato plants in should be a minimum of 5-gallon pots to allow for a depth of 12” of potting soil. This would only be suitable for cherry tomatoes and other dwarf varieties.
The bigger a vine you plan to grow, the bigger the container should be.
A 20-gallon container can support roots of plants that grow as high as 8’ to 10’ in height. Naturally, for those heights, you will need to support them with stakes or trellises.
Larger containers are ideal for indeterminate tomato plants as they have the depth for increased soil and have the space to include stakes within the container to support vertical growth.
20-gallon pots are generally up to 20” wide so some types of tomato plants, such as the Roma, which is a wide grower, will need more spacing between the pots.
Spacing Requirements for Saving the Seeds of Heirlooms
Heirloom seeds are expensive and that’s because they’re proven winners for taste, yield, texture and generally great tasting juicy tomatoes.
With an heirloom tomato variety, you know what’s going to grow. They produce reliable yields with the same results consistently.
A German Queen heirloom, as an example, grows between 4’ to 6’ in height, produces beefsteak tomatoes with a sweet taste that’s ready to harvest in around 80-days. Save the seeds and you’ll get the same result next season.
Rather than consistently buying new heirloom seeds, you can save the seeds from one year’s harvest to plant the next year, knowing you’ll grow the same type.
Or will it be?
Heirloom seeds are only the same type if they don’t get cross-pollinated. The only way that can happen is when two plants of different types are in bloom together.
Only planting the same variety is the best protection from cross-pollination. Spacing at 10’ minimum is the next-best protection.
Another option is bagging using blossom bags, and another is to plant nectar and pollen-producing plants that will bloom at the same time as your tomatoes.
Insects are attracted to tomato plants for their protein. Not nectar, so if you plant flowering plants between different varieties, bees and other pollen-seeking insects are more likely to feed on them and leave your tomatoes alone.
If you need to plant more than one variety of heirloom though, 10’ of spacing should be sufficient to prevent cross-pollination. 25’ if you can manage it but most home gardens aren’t that big.
Blossom bags would be more suitable for the home gardener.
Tomato Plant Spacing FAQs
Can tomato plants be planted closer together in raised garden beds?
No. Whether you grow your vegetables in ground soil, containers, or a raised garden bed, the depth of soil isn’t the issue. The real threat to tomato plants is a lack of sunlight, and reduced air circulation. Reducing air flow increases humidity and that increases the risks of pests and diseases. Both can kill tomato plants.
Can other vegetables be planted in the space between tomato plants?
Absolutely. And they should be. Indeterminate tomato plants can be pruned closer to the ground level to maintain their fruiting higher up, and you can maximize lower space by growing shade-preferring plants under the canopy of the foliage on tomato plants. Lettuce, carrots, asparagus, celery, cucumber and similar low-growing vegetables do well as companions for tomatoes.