Growing tomatoes in pots is a great way to enjoy fresh tomatoes without taking up a lot of space. All you need is a pot (or two), some seeds, a bit of fertilizer, and some high-quality potting soil.
I wanted to share my method for how to grow tomatoes in pots, along with how I choose the right size pots for tomatoes, and a few things to be aware of when growing tomatoes in containers vs in the ground.
Gathering Your Materials
To successfully grow tomatoes in containers, you’ll need the following:
- A large pot (see below for help choosing size)
- A high-quality potting mix
- Tomato seeds
- Quality tomato fertilizer
- Dolomite lime
Let’s walk through each one and talk about what to keep in mind when selecting your materials.
1. Choosing Your Pots
You can’t just pick a random pot and get started. You want to make sure it has good drainage and is large enough.
Drainage holes are critical, so if your pot doesn’t have them you’re going to want to drill your own holes in the bottom. Otherwise, your plant’s roots will be sitting in the excess water which can cause root rot and a whole host of other issues.
You can grow them in clay pots, plastic pots, or even a grow bag. But you’ll want to be sure it offers your plant’s roots enough space to flourish.
What Size Pots Are Best for Growing Tomatoes?
You want to choose a pot that has at least a square foot of space for the roots to grow. But, if you want a really healthy plant, choose one that’s double that size and at least 2 square feet.
For you to properly grow indeterminate tomatoes, you want to use a larger one – here is the rule of thumb I follow:
- Indeterminate Tomatoes – 24-inch pot
- Determinate tomatoes – 18-inch pot
If you’re using a grow bag, I would use these ones, as they have the right capacity in gallons and are durable enough to hold your tomato plants and that much soil.
2. Good Quality Potting Soil
The potting soil you use for growing tomatoes is important. Because you’re not giving the plant as much room to grow, you want to pick a good potting soil mix.
This is my favorite potting soil for growing in containers, as it checks all the boxes and has a small amount of fertilizer in it to get the plants enough nutrients from the start.
3. Tomato Fertilizer & Lime
I like to use a balanced organic fertilizer like this one. It has all of the nutrients your tomatoes need, and doesn’t have any weird chemicals or GMOs in it either which is why I like it.
Tomatoes are prone to something called blossom end rot, which essentially means your tomato fruits might turn brown and mushy on one side. To combat this, add calcium to your soil.
Some people put an antacid tablet (yes, really) into the soil before planting their seedlings. You can do this, or add some ground-up eggshells, add Epsom salt, or just add dolomite lime granules to the soil. Any of these will work, but adding some form of calcium to the soil ahead of time can help tremendously.
4. Tomato Cages or Trellis
Tomatoes grow best when they have some kind of support structure. While most often this is a tomato cage, you can also create a DIY tomato trellis that’s a bit easier to manage.
Since you’re growing in a small space, you don’t necessarily need a trellis, but it’s a good idea to put the pot near a railing or structure that it can lean on.
5. Tomato Seeds [+ The Right Type of Tomatoes]
While this step seems obvious and one to skip over, it can be a little more complicated than you think.
There are two overarching types of tomatoes: Indeterminate tomatoes and determinate tomatoes.
Indeterminate tomatoes that get very big, often topping out at a height between 6 and 8 feet tall. Indeterminate plants produce fruit throughout the growing season, and you can keep harvesting them as the plant matures. Some indeterminate tomato varieties include beefsteak and San Marzano tomatoes, although some of those are also determinate.
Determinate varieties are usually the smaller bush varieties of tomatoes, where the plants stay small, and instead of getting a continuous harvest throughout the season, all of the fruits grow at once. Some determinate plants include Roma tomatoes and some varieties of cherry tomatoes.
What Tomato Varieties Grow Best in Pots?
Determinate tomato varieties are the better option for container gardening because they do well in small spaces. Any tomato labeled “bush” or “dwarf” will do great in small spaces and pots.
While you can grow indeterminate varieties in tomato containers, just be aware that they get much larger than their counterparts, so give them at least 1-2 feet of space outside the container on all sides for proper growth.
Here are some great varieties for container gardens:
- Gold Nugget (cherry tomato variety)
- Bush Beefsteak (beefsteak variety)
- Plum Regal (Roma variety)
There are a lot of options to choose from, so have fun with it!
How to Grow Tomatoes in Pots [Step by Step]
Now that we have all of the materials we need, let’s go ahead and walk through the steps to plant tomatoes in pots.
1. Choose a Sunny Location
Tomatoes love being in the sun, so you want to make sure you choose a growing location that gets 6-8 hours of direct sunlight a day. You also want to make sure that this location is somewhat close to a water source. While you can put water in a watering can or use a longer hose, it can get heavy, so you don’t want your plants super far away.
2. Add Potting Soil to Your Pots & Add Fertilizer
Fill up your pots about halfway with your quality potting soil. Sprinkle in your tomato fertilizer and dolomite lime or another source of calcium. Mix the soil around so you get a decently even mixture of these 3.
3. Remove the Bottom Branches of Your Plants
Tomatoes do really well when you plant them deep. By removing the other stems, you’re making the base of the plant stronger and allowing it to grow thicker.
If you’ve ever noticed the little hairs on the stem of a tomato plant, those are actually the start of roots. Once you plant your tomato plant deep in the soil, those hairs will form roots and build a stronger foundation for the plant.
I remove almost all of the branches aside from 2-3 at the top. This allows more roots to form.
Note: If you’re growing a determinate variety, you might opt not to remove the bottom branches to allow the plant to keep growing. I would still do it as I’ve had good success with it, but this is optional for determinate varieties.
4. Plant your Tomato Seedlings
Plant your tomato seedlings in the pot deep enough so that only the 2-3 branches that are left are above the soil. You want to keep the leaves from touching the soil though as that can spread disease quickly.
Plant them deep enough to cover most of the stem, but high enough to keep any leaves from touching the soil.
5. Add the Remainder of the Soil on Top
Add the rest of the potting mix to the container, as to cover up the stem as I mentioned above. Water your tomato plant and make sure the drainage holes aren’t clogged up – you should see some water come out the bottom eventually.
6. Add Some Support
If your tomato plant is going to be in a plant that doesn’t have a wall or railing nearby, you might want to consider adding tomato cages or another type of trellis for them to lean on.
Tomatoes want to grow horizontally like a vine, especially indeterminate or cherry varieties, so consider adding a tomato cage like this one around the plant.
7. Water Regularly
If you’re thinking you can water tomatoes in pots like you do tomatoes in the ground, think again.
Soil in containers is going to dry out much faster than soil in the ground, so you’ll need to be diligent about your watering schedule.
Check the soil every day to see if it needs water. I would honestly just get in the habit of watering every morning (unless its raining) to keep the garden soil moist, but not wet. This is especially true in the summer on those hot days, or if it’s really windy, as wind will dry out the soil quickly as well.
How much you water tomatoes is important as well, and you want to make sure you are watering only the soil, not the leaves. I like to use a watering wand to make sure I’m not splashing water up onto the leaves which can cause them to get plant diseases or encourage pests to take root.
8. Add Fertilizer As Needed
Adding fertilizer at the beginning when you first transplant your tomatoes is important, but they’re going to need more than that.
Follow the instructions on your fertilizer container, but typically it’s every 10-14 days that you’ll need to add fertilizer.
9. Harvest Your Tomatoes
After 8-12 weeks, your tomatoes should be ready to harvest. I determine when to pick tomatoes based on their coloring. Usually when they are starting to turn pink is the best time to pick them. Waiting until they’re fully ripe can lead you to beat the birds to them and other animals that eat tomatoes.
When to Transplant Tomatoes Outdoors
Tomatoes are a sun-loving plant and need quite a bit of heat to grow effectively. You want to wait to transplant them outside until the night temperatures are consistently above freezing (more like 40-45 F).
While waiting until your last frost date is a good rule of thumb, sometimes Mother Nature wants to throw us all for a loop and give us a deep freeze later that year, so check the 10-day forecast and make sure nighttime temperature won’t drop below 40-45 degrees.
How Deep Do Containers Need to Be For Tomatoes?
Containers should be at least 18 inches deep to give roots enough room to thrive in the container.
Do Tomatoes Grow Better in Pots or in the Ground?
Both methods work well for tomato plants. Container tomatoes can provide you with fresh tomatoes even if you don’t have a ton of space.
I personally think growing them in the ground or in raised bed soil is easier, as the soil stays moister and your plants’ roots get more exposure to worms and worm castings which add a lot of nutrients.
Growing tomatoes in pots is more labor-intensive in my opinion, but if you don’t have a ton of space, it’s better to have tomatoes than to be eating store-bought ones.