
A Guide to Growing Tomatoes on a Balcony
Urban gardening can be immensely satisfying. Your balcony is a perfect spot for cultivating a variety of foods, including tomatoes.
If you’re thinking of growing tomatoes on balcony, this guide covers the different facets, tips, and techniques to steer you in the right direction.
Here’s what you need know to grow healthy tomato plants for large harvests.
The ideal balcony for growing tomatoes
Let’s face it; no two apartments are created the same. So, what’s the perfect spot like? There’s one main thing to consider – access to sunlight.
Your tomatoes need adequate exposure to direct sunlight for approximately 6-8 hours a day.
Pay attention to the direction of the sun. However, remember the balcony could be facing the full sun but receive less sunlight throughout the day because of the obstructing trees, structures, and buildings.
On a sunny weekend, be sure to take your time to observe how light and shadows fall on your balcony.
It’s easy to overestimate the amount of sunlight your spaces receive. To take the guesswork out of the way, we recommend using a sunlight recorder or meter.
Picking tomato pots and containers
The size of the pot or container you choose for growing tomatoes matters a great deal. One mistake beginners make is using small containers. At first, this might not seem like an issue. However, they can significantly affect the growth rate and production of your tomatoes. That’s because the small spaces restrict roots. What’s more, you’ll need to water them more often.
Therefore, the best course of action is to go for bigger containers. In line with that, you’ll want to use containers or pots with a diameter of at least 18 inches. The depth should be around 24 inches.
Tomato containers of this size won’t easily fall over, and they hold more soil, water, and nutrients. Plants with large spaces and an adequate supply of nutrients tend to develop strong roots.
Nevertheless, ensure the pots have enough drainage holes.
When it comes to types of tomato pots, you may want to stay away from metal and glass containers. You can also add black plastic containers to that list. These pots easily become hot when exposed to the sun.
Types of tomatoes suitable for balcony garden
Did you know there are thousands of tomato varieties out there? With a large container and spacious balcony, you can practically grow all types of tomatoes. However, some specific varieties are easy to grow and produce more fruits than others.
If you have limited spaces, determinate varieties could be your best option.
Indeterminate ones spread and become too tall. They might give your neighbors a reason to complain.
With determinate tomatoes, they usually don’t grow more than four feet. They also crop quickly, require low care, and produce heavily within a short period.
Many gardeners opt for the cherry-sized tomato varieties, such as Sweetheart of the Patio, Tumbling Tom, MicroTom, and Red Robin.
For those who want to plant fist-sized tomatoes, try growing tomato varieties like Patio Princess, Bush Goliath, Early Girl Bush, Totem, and Celebrity Tomato.

How to Grow Tomatoes on a Balcony
Having covered the basics, it’s time to walk you through the process of growing tomatoes.
1. Preparing potting soil
Tomatoes flourish in well-prepared fertile soil. Don’t just fill the tomato pots with only the garden soil you collect from your planting beds.
Such soil is usually over compacted, something that affects the infiltration and drainage rate of water. This high-density soil is also prone to disease-causing organisms, which stay in the soil for an extended period.
Making a high-quality potting mix is easy.
Alternatively, you can buy the ready-made potting mix. With this option, the soil already has fertilizer or slow-release nutrients.
If you want to make potting soil, your composition will typically include a mixture of compost materials, peat moss, perlite, and light soil. Make sure you add a slow-release fertilizer to the soil before transplanting the tomato plants.
Soil pH Levels
Many beginner gardeners forget about the pH levels of the soil. The plants thrive in soil with a pH of 6.0 to 6.8, which is slightly acidic. If you want sweeter tomatoes, you can increase pH up to 7.5 once the tomatoes show signs of ripening.
How to adjust soil pH for tomatoes
If the soil is too acidic, add wood ash. Alternatively, you can use dolomite lime.
When it is alkaline soil, you can bring down the pH level using sulfur or an ammonium sulfate fertilizer. Check this at your nearest garden supply center.
2. Planting tomatoes
You can begin transplanting the tomato plants as soon as they form two true leaves.
When planting the seedlings, make sure the holes cover the plant up to the first leaf. That’s about two-thirds of the stem.
The deeper the roots go, the faster they will collect nutrients. More nutrients facilitate the growth of your tomato plants.
Do not transfer several seedlings into one container. If you have a bigger tomato pot, make sure to space the plants one inch apart.
Planting one plant per pot means the tomato will not be competing for water, nutrients, and space. With less competition, the plants tend to grow faster and healthy.
3. Watering your plants
It’s advisable to water the seedlings deeply and leave them for an hour before transplanting.
After digging the holes, add water. You can start planting as soon as the water has been absorbed into the soil.
Water the plants once more, preferably within 15 minutes of transplanting. It helps offset the transplanting shock. However, don’t make the soil soggy or saturated.
Before the plants are established, you may need to monitor them at least once a day for about 2-3 weeks.
How often you water your plants is subject to many factors, including tomato container size, potting soil, humidity, wind, and heat.
Watering tips
We recommend pushing your finger into the soil, ideally an inch or two. If you feel the soil is dry, supply more water.
Generally, the plants should get at least 1 inch of water weekly. You may need to supply more, especially during the hot months. As plants enter the mid-season, they might need watering at least every day.
Irregular watering or too little water is a recipe for disappointment. It can cause blossom end rot.
When watering your tomatoes, make sure you deliver water to the base of the plant. The problem with overhead watering is that it can lead to fungal diseases like blight.
Reduce the frequency of watering when the fruits start ripening. That way, plants can produce fruits with a good concentration of sugars, thus providing a better flavor. However, don’t starve the plants until they start to wilt.
4. Adding a layer of mulch
When it comes to mulching, you’re spoiled for choice. Many gardeners stick to organic mulch materials, such as hay, grain straw, wood shavings, shredded bark, and fallen leaves.
A layer of mulch preserves moisture in the soil, keeps wet soil from splashing onto the leaves, and protects the lowest growing fruits from rotting when they rest on the ground.
However, don’t add mulch to plants until they are established.
5. Fertilizing
Growing Tomatoes On a Balcony You’ll still need to supply your plants with additional fertilizer, even if you used a pre-fertilized potting mix.
The amount of fertilizer in many potting mixes starts to drop typically after the first two weeks of planting. It’s because tomatoes are heavy feeders. As such, a regular supply of nutrients is imperative for a high yield.
You can start fertilizing after two weeks. Apply a small amount of liquid organic fertilizer every week. Be sure to follow the instructions on the packet.
Others balcony gardeners wait until the plants start producing fruits, especially if the plants are looking healthy.
However, sometimes plants can look healthy but produce fewer flowers or fruits. That’s a sign of high levels of nitrogen in the soil. In such a case, we advise you to pinch the tips and then apply a phosphorus fertilizer.
If you are dealing with blossom end rot, feed your plants with a fertilizer rich in calcium. Or, you can add finely crushed eggshells to the soil.
6. Removing suckers
Leaving the tomato suckers to grow and become another stem with branches creates competition for nutrients.
Even though you may have more fruits from one plant, the tomatoes grow in smaller sizes. Some suckers won’t bear fruits even after draining the nutrition of the original plant.
Therefore, it’s best to prune out the suckers.
7. Supporting the plants
For the determinate varieties, you can use conventional tomato cages and stakes. With tall tomato varieties, we recommend trellis or more sturdy cages.
Wrapping Up – Growing tomatoes on a balcony
While growing tomatoes on balcony look easy, a few wrong decisions can twist your experience to less rewarding.
And sometimes you can do everything right, but not achieve the healthy, large harvests because of factors you’re not in control of. Therefore, don’t beat yourself up.
We hope the above tips and techniques help you get the most out of balcony gardening.
Happy gardening!