How to Use Planters for Tomatoes

Tomatoes growing in a dark green EarthBox container gardening system

According to the United State Department of Agriculture, the average American eats about 31 pounds of tomatoes annually. That’s second only to potatoes. So, wouldn’t it be nice to have a ready supply outside your door if you're a tomato lover? Well, you can by using a tomato planter. Here’s how to use planters to grow your own tomatoes.

What are Tomato Planters?

If you aren’t familiar with tomato planters, they’re gardening containers used specifically for growing tomatoes. They come in various shapes and sizes and can be made from plastic, wood, or metal. And you can use them for indoor or outdoor container gardening.

For example, EarthBox Original planting boxes are perfect for a tomato planter. They have mulch covers that prevent weeds and accessories like casters for easy transport, plus fertilizer and potting mix. So, you get a full-blown planting system to ensure your success.

Gardeners often use tomato planters to improve drainage and increase the sunlight they receive. Tomatoes are sun lovers, after all. And because tomato plants get large and bushy, some planters come with cages or trellises to help them grow upright.

The Advantages of Tomato Planter Boxes

Tomatoes grow well in traditional gardens. That approach provides natural growth because the plant’s roots can grow deeper and wider, giving your plants more stability and nutrient access.

But if your growing space is limited or you have none, gardening containers open the door for growing your own. And that’s one of their chief advantages – tomato planters save space. That said, tomato planters have other advantages.

  • Less Work: Unlike traditional in-ground gardens, tomato planters require less work. That’s because container gardening companies have developed optimized growing systems. For example, EarthBox manufactures planting boxes that require no weeding or digging.
  • Bigger Yields: The best tomato planting boxes can double the yield of a traditional in-ground garden. That’s possible due to how container gardening systems are scientifically engineered. They’re designed using tried-and-true commercial growing concepts that tend to produce better results and bigger yields.
  • Improved Drainage: Tomato planters typically have drainage holes that allow excess water to drain away from the roots. Drainage is essential to prevent root rot and allow salt accumulation to exit the gardening container.
  • Increased Sunlight: You can place and move tomato planter boxes where they’ll receive the most sunlight to help improve growth and yields.
  • Soil Quality: With a gardening container, you can control your soil’s quality better, ensuring your plants receive the proper nutrients and pH levels.
  • Disease and Pest Control: The ground harbors potential concerns from disease and pests. But tomato planters offer greater control. First, you can isolate your plants from areas of concern. Second, you can treat your plants more quickly because they’re in a contained space.
  • Harvesting: With planters for tomatoes, harvesting is easy. For example, you can walk out to your patio, pick the tomatoes, and go back into your home. No need to shuttle to a gardening area.
  • Aesthetics: Some tomato planters have decorative designs to dress up your space. Even if they don’t, having tomato plants on a balcony or patio adds greenery, not to mention the burst of colors as the tomatoes ripen.
Tomatoes growing in a green gardening container supported by a staking system

How to Grow Tomatoes in Planting Boxes

The beauty of planting tomatoes in a gardening container is that it’s easy. Just follow these steps:

  1. Select the Right Tomato Variety: Some tomato varieties are better suited for container gardening. More on that briefly.
  2. Use the Right-Sized Planter: Make sure your tomato planter can handle your selected variety. Remember, tomato plants get reasonably large. Moreover, the larger the gardening container, the better the roots can establish.
  3. Use Quality Potting Soil: Fill the tomato planter with high-grade potting soil that drains well. Make sure to always follow any planter-specific guidelines if they’re provided.
  4. Plant: Once you’ve added the soil to the planting box, make a hole in it large enough to accommodate the plant’s root ball. Then, plant it and cover it with soil. Again, always defer to your planter’s instruction manual since the steps can vary.
  5. Water: After planting, water your plant. When watering, it’s best to water until it drains out the container’s bottom. Don’t overwater your tomato plants. You’re better off watering less frequently. But when you do water, ensure deep water until it drains from the tomato planter.
  6. Fertilize: Tomato plants need frequent fertilizing to reach their potential. And remember, nutrients can drain from the planter. So, fertilize your plants every two to three weeks or as recommended by the tomato planter company.
  7. Support Your Plants: Tomato plants can sprawl. Keep them contained using tomato cages or stakes. Besides helping control the plant’s growth, supporting your plants also prevents them from falling over as the tomatoes begin to grow.
  8. Check for Issues: Keep an eye out for signs of pests or diseases, and then take immediate action.
  9. Harvest: Now comes the fun! Once your tomatoes ripen, you can pick them and enjoy them.

Remember, tomatoes need at least six hours of sunlight daily. Make sure your tomato planter is in the right place. If not, move it.

What are the Best Tomato Varieties for Planters?

You can grow different tomato varieties in gardening containers, but some are better suited. Here are a few of the best tomatoes for planting boxes:

  • Determinate Varieties: Also called bush tomatoes, they’re compact and typically don’t require staking. They work well in smaller planters. Popular varieties include Patio, Tiny Tim, and Roma.
  • Cherry Tomatoes: These small tomatoes are perfect for container gardening. Moreover, they’re easy to grow and produce prolific yields. Some popular cherry tomato varieties include Sweet 100, Sungold, and Tiny Tim.
  • Container-Specific Varieties: Believe it or not, some tomato varieties are bred specifically for container gardening – Tiny Tim and TomTato, Micro-Tom, and Tumbler, among others.
  • Dwarf and Miniature Varieties: Any smaller or compact variety makes it a good selection for container gardening. Popular types include Cherry Cocktail, Golden Nugget, Golden Grape, Tumbling Tom, Baby Red Pear, Yellow Canary, etc.

It’s a good idea to check with a local nursery or gardening expert to find out which varieties are best suited for your area. At the Gardening Channel, you can also check out some better tomato varieties for container gardening.

How Many Plants Should I Use in a Tomato Planter?

Two factors impact this decision. The first is the size of your gardening container. The second is the tomato variety.

Determinate varieties tend to be smaller and more compact, allowing you to plant them closer together. On the other hand, indeterminate varieties (vining tomatoes) get larger and more sprawling. So, you’ll want to err on fewer plants per gardening container.

However, here are some guidelines.

  • Small Tomato Planters: With a smaller planter for tomatoes (12 inches), you can plant one safely, perhaps two.
  • Medium-Sized Tomato Planters: Planters in the 20-inch range can hold two to three tomato plants.
  • Large Tomato Planters: A 30-inch planter holds four to six tomato plants. Indeterminate varieties, also called vining tomatoes, tend to be larger and more sprawling, so they need more space.

Overcrowding plants in a gardening container creates resource competition, leading to poor growth and low yields.

Common Issues with Tomatoes in Planters

Even though you have better control of your plants in a tomato planter, you can face issues. If you see problems with your plants, they could relate to one of these common concerns:

  1. Overwatering: Tomatoes in planters are susceptible to overwatering because the soil can become waterlogged. When that happens, your plants become oxygen-deprived, resulting in root rot and death. In addition, stems and leaves may become yellow or develop bumps and even fall off.
  2. Underwatering: The opposite can happen if the soil isn’t consistently moist. Plants will wilt, droop, and split. They can also develop blossom-end rot (BER) which causes a dark, sunken area on the lower blossom end of tomato fruits. It’s caused by a calcium deficiency generally induced by plant water supply fluctuations. Consider a calcium nitrate additive which will help prevent BER.
  3. Lack of Sunlight: Tomatoes need lots of energy to grow large and produce edible fruit (yes, tomato is a fruit). Without sufficient sunlight, they may not grow to their full size and produce less, if any, harvestable fruit.
  4. Pests: Tomatoes are susceptible to aphids, whiteflies, and tomato hornworms, which damage the leaves and fruits. You can use an insecticide or combine liquid dish soap with water and spray the plants.
  5. Disease: Your tomato plants can suffer from various diseases – anthracnose, black mold, blight, fusarium wilt, powdery mildew, and more. Again, you can spray the plants with dishwashing soap and water. Or try an anti-fungal treatment with chlorothalonil.
  6. Heat Stress: High temperatures can cause the fruits to crack and leaves to wilt. You can reduce your chances of this issue by mulching, deep watering, and providing shade.
  7. Nutrient Deficiencies: Tomatoes in planters generally require more fertilizer than those in the ground. Common deficiencies relate to phosphorous, nitrogen, and iron. As mentioned, fertilize your plants every two to three weeks.
  8. Lack of Support: Left to their own devices, heavy fruits can weigh your plant’s stems, leading to breakage. Equally important, you can incur damage from slugs, diseases, and fruit spoilage if tomato fruits lay on the ground.

Supporting Tomatoes in Gardening Containers

As mentioned, tomatoes need proper support to perform their best. You can accomplish that in several ways.

First, tomato cages are readily available at nurseries and garden centers. The circular frame places around the plant and supports the stem as it grows. They come in various sizes and materials.

Make sure your cage is at least three-feet high. The legs of the cage should reach the bottom of the tomato planter. You can shape the legs to fit your gardening container.

Second, you can stake plants. Insert a wooden or metal stake in the soil next to the plant. Then, tie the stem to the staking with twine or a tomato tie.

You’ll need to repeat the exercise as the plants grow taller, typically every 10 to 14 days. Ideally, you should tie the center of the plant to the stake every six to eight inches to keep it upright.

Staking uses less space than tomato cages. Some manufacturers, like EarthBox, offer a staking system with their planting boxes.

A 5 foot EarthBox Staking System being used to support tomatoes growing in a container garden

Fertilizing Your Tomatoes in Container Gardens

The frequency of fertilizing tomato plants depends on the fertilizer type and the plant’s growth stage. Always follow the fertilizer recommendations provided by tomato planter’s manufacturer.

For your basic gardening containers, you’ll want to hit the plants with a balanced liquid fertilizer every two to three weeks for seedlings and the early stages of plant development.

Once established, you can begin to fertilize every two to four weeks again with a liquid fertilizer.

During the fruit-setting stage, you should fertilize every two weeks with a fertilizer high in potassium and phosphorous. These nutrients encourage fruit growth.

After fruit-setting, your tomato plants benefit from fertilization every two to four weeks.

If you’re using organic fertilizer, it’s best to add it to the soil at the time of planting and then again every four to six weeks.

Be careful not to over-fertilize, or you can damage your plants. For example, if you notice leaves turning yellow or the plant wilting, it’s a sign that you may be over-fertilizing. You can reduce the frequency or dilute the fertilizer solution to address the issue.

How Long Does It Take Tomatoes to Grow in Planters?

Several factors influence the growth rate of tomato plants, including the variety, weather conditions, and plant care. But here are some guidelines:

  • Germination: If you’re growing from seeds, they germinate within one to two weeks.
  • Seedling Stage: Seedlings typically grow to four to six inches within four to six weeks.
  • Vegetative Stage: Once your tomato plants hit this stage, they grow more rapidly. The phase lasts for six to eight weeks, depending on the variety.
  • Fruit-Setting Stage: Once mature, plants begin to set fruit. That happens anywhere from four to eight weeks, again based on variety.
  • Harvesting: You guessed it – variety determines your harvest date and weather conditions. Some tomatoes are ready for harvest in as few as 50-60 days. Others take up to 80-90 days for harvest.

When growing in tomato planters, it may take slightly longer to harvest. First, your planter for tomatoes may dry out more quickly if you aren’t diligent about watering. Second, temperatures inside the planter can get higher than the surrounding air, impacting the plant.

Keep an eye on weather conditions and adjust when needed. For example, if it’s dry, make sure you water deeply more frequently. On the other hand, give your plants some shade if you have sweltering days.

Ready to Try Your Hand at Planting Tomatoes in Containers?

Caught the fever and are ready to try growing and harvesting your very own crop of luscious tomatoes?

Fortunately, EarthBox makes it even easier to get started. We offer a tomato growing kit. You get everything you need for successful gardening:

  • Tomato Planter
  • Staking System
  • Wire Ties
  • Fertilizer
  • Soil

We include instructions for setting things up. Best of all, the sub-irrigated tomato planter and the growing system are 100% guaranteed.

You can also access container gardening tips to help you succeed at growing tomatoes in our planting boxes:

Our planting boxes and gardening systems are top-rated. We’ve helped customers successfully grow vegetables, fruits, herbs, and tomatoes since 1994.

Tomatoes, carrots, and herbs being grown in different EarthBox gardening containers