How to Grow Tomatoes on a Balcony (Expert Advice)

If you don’t have to have a large garden or even any garden at all you can grow delicious, flavorsome tomatoes in large pots or tubs on your balcony or out in your patio area.

To grow tomatoes successfully on a balcony, all you need is a large pot, the right tomato variety, an adequate amount of sunlight, and the determination to tend to your plants to ensure that they produce lots of juicy tomatoes.

Follow these tips to grow the tastiest tomatoes on your balcony.

tomatoes grown on a balcony

Choose the right Variety

There are countless varieties of tomatoes that can be grown by home gardeners. Fortunately, there are also numerous ones that will grow quite happily in pots. In fact, you can grow almost any variety in a pot, except some will require heavy-duty staking, which may not be ideal.

For this reason, determinate tomatoes are ideal for growing in containers as they’re more compact in size and don’t grow nearly as tall as indeterminate ones. If this has already confused you, here’s a quick explanation.

  • Determinate tomatoes are also commonly referred to as bush tomatoes. They grow to a certain height, up to 2 or 3 feet (60 to 90 cm), and then they stop growing and start producing flowers and fruits. In general, all the fruits ripen at once, and you’re unlikely to get more than one harvest per season.
  • Indeterminate tomatoes just continue to keep growing upwards throughout the season. For this reason, they need really good staking to keep the main stem upright. These tomatoes will crop continuously throughout the season, so you’ll get crop after crop of ripe tomatoes until the weather cools off. These types of tomatoes also require regular pruning to keep them under control and fruiting well.

Here’s a good selection of determinate tomatoes that are ideal for growing on a balcony:

Tomato VarietySize of FruitType of Tomato
Bush BeefsteakLargeBeefsteak
CelebrityMediumSlicing
ChiquitaTinyGrape
Defiant PhRMediumSlicing
GalahadMedium to LargeBeefsteak
GlacierTinyHeirloom
Gold NuggetTinyCherry
Grand MarshallLargeBeefsteak
Mountain Fresh PlusLargeSlicing
Mountain MeritLargeSlicing
Oregon SpringMediumSlicing
PaisanoSmallPaste
Plum RegalSmallPlum
PolbigMediumSlicing
SkywayLargeBeefsteak
Sunrise SauceSmallPaste
Tasmanian ChocolateSmallHeirloom
Valley GirlMediumSlicing
Washington CherryTinyCherry

Choose the right Spot on your Balcony

As you may already know, tomatoes like to grow in a nice sunny spot. In fact, for the best harvest, your tomatoes should be exposed to around 6 to 8 hours of sun every day.

For this reason, you want to choose the sunniest spot on your balcony to grow your tomatoes. In general, the morning sun is best, but if your balcony is shaded in the morning, the bright afternoon sun will work as well. You’ll find that tomatoes that don’t get at least 6 hours of sun daily will produce less fruit, and the fruit will take longer to ripen.

The advantage of growing tomatoes in pots is that you can move them around to follow the sun during the day. That’s another reason why it’s better to grow determinate or bush tomatoes on a balcony because these will be easier to move.

If you are struggling with your tomatoes getting enough sunlight, you can supplement this by installing a grow light that you can turn on for several hours each day.

Choose the correct Pot

For tomatoes grown in a pot, you want to ensure that the pot is large enough to accommodate the root growth of your plants. If you are going to be moving the pot around to catch the available sun, you also want to ensure that it’s fairly lightweight. Alternatively, you can get pot stands that have wheels on them to make this task easier.

It’s also important to ensure that the pot has adequate drainage holes. You don’t want to have the roots constantly sitting in water because this will eventually cause them to rot.

Here are the basic requirements for choosing the right pot:

  • The pot should have a minimum of 12 inches in diameter but can be up to twice that size.
  • The pot must have adequate drainage holes.
  • Avoid black plastic pots as these can heat up fairly quickly when exposed to full sun.
  • Terracotta pots are great, but they will dry out faster because they are porous.
  • Ceramic or stone pots are good too, but they are heavy and will need some assistance, such as a movable plant stand if you want to move them around.
  • Large grow bags are also excellent, especially if you place them on a movable plant stand.

Select a Good Quality Potting Mix

Once you’ve selected the pot or pots that you want to grow your tomatoes in, you’ll have to fill them. You want to select the best quality potting mix that you can afford. Many garden centers have specially formulated potting mix that is designed for growing vegetables.

Avoid using garden soil as this is generally too heavy and will become compacted. Garden soils can also harbor diseases such as blight or pests such as nematodes. Therefore, the soil that you use for your pots should be nice and open and contain lots of nutrients.

You can make your own mix by combining well-aged compost with another material such as perlite to assist in drainage. Even well-composted wood chips will work well to improve the aeration of the compost and the drainage.

Plant your Tomatoes Correctly

Whether you’re growing your tomato plants from seed or from transplants that you’ve purchased from the garden center, you want to ensure that you plant them correctly for the best results.

Here’s what to do:

Tomatoes Grown from Seeds

  • Sow two seeds in one pot only. You want to end up with just one plant per pot. Sowing two seeds ensures that you’ll have at least one plant if one of the seeds fails to germinate.
  • Plant the seeds in the middle of the pot around ¼ inch (6 mm) deep.
  • Firm the soil to ensure good contact with the seed.
  • Water the soil where the seeds have been planted, being careful not to dislodge them.
  • Keep the seeds moist until they germinate. This should only take around 7 to 14 days.
  • If both seeds germinate, discard the weaker seedling.
  • Keep your seedlings watered on a daily basis.

Tomatoes Grown from Transplants

  • Make a hole in the center of the pot that is deep enough to accommodate both the roots of the seedlings and around two-thirds of the stem. Burying a portion of the tomato stem is common practice because roots will grow from the buried section of the stem, and this will give the plant a good start.
  • Take the seedling out of its current pot and place it in the hole. Remember that you only want one tomato plant per pot.
  • Press the soil gently around the base of the plant and water in.
  • Place some straw mulch or similar on top of the soil. This helps to stop the moisture from evaporating too quickly. It’s a good idea to refresh this mulch as it decomposes. It will add some additional nutrients to the soil as it breaks down.

Add some Support to your Tomato Plants as they Grow

Even determinate or bush tomatoes will require some support as they grow. This will stop the plants from toppling over once they’re heavy with fruit. It will also provide some much-needed support for the fruits as they mature and ripen.

Here are some of the better ways to support your balcony-grown tomato plants:

  • Tomato cages. For tomatoes grown in pots, tomato cages are ideal as long as they’re tall enough to accommodate the growth of the plant. They work really well with determinate tomatoes but are not ideal for indeterminate varieties. They are also easy to get hold of and install.
  • Create a teepee with stakes. Another way that you can support your growing tomatoes is to create a teepee with some garden stakes and twine. Use 3 or 4 garden stakes placed at equal intervals around the edge of the pot. Bring the tops of the stakes together and bind them with some garden twine. You can even wind some twine at intervals around the outside of the stakes to keep the tomato plants contained.

Note: Make sure that you install the supports at the same time as planting to ensure that you don’t disturb or damage the roots of the young plants.

Keep your Tomatoes Well-Watered

Tomatoes are relatively thirsty plants and don’t appreciate drying out. Because you are growing your tomatoes in pots, you’ll have to be vigilant with the watering because the soil in pots can dry out quite quickly.

Tomatoes prefer moist but not waterlogged soil. In the heat of summer, this may mean that you have to water your pots at least twice a day. A good rule of thumb is to check the top one inch of soil with your finger. If it feels dry, then it’s time to water your plants.

You could also set up a drip irrigation system for your tomato plants. This will supply a constant water supply to your plants and means that you don’t have to be out there watering constantly.

Even if there’s no handy tap near your balcony, you can use gravity feed and a water reservoir to keep your tomatoes well hydrated. Here’s what to do:

  • Create a water reservoir using a large bucket or plastic tub.
  • Place this on some type of stand so that it sits slightly higher than the soil level of your plants.
  • Use some black plastic hose as the main supply line.
  • One end of this needs to be inserted into the reservoir, and the other end should have a cap put on it.
  • Along this hose, insert some thinner pieces of hose and attach drippers to the ends of these.
  • Depending on the size of your pots, place one or two drippers in each one.
  • Fill the reservoir with water and inspect the flow to each plant. You may need to adjust this over a few days until your plants are getting all the water that they need.
  • Now all you have to remember to do is to fill the water reservoir whenever it gets low.
tomateoes grown on a balcony

Keep your Tomatoes Well-Fed

Not only are tomatoes thirsty plants, but they’re also heavy feeders. If you want your plants to produce a massive harvest, you’ll have to keep them well fed. In the beginning, your plants will get their nutrients from the quality potting mix or compost that you’ve used. But, these nutrients will soon run out, and you’ll have to replace them.

Ideally, you want to use a tomato fertilizer as this will contain the essential nutrients that your plants are going to need. It will also contain essential minerals such as calcium that will prevent blossom end rot on your tomatoes.

When looking at fertilizer packs, ensure that the one you use is fairly well-balanced. It should contain close to equal amounts of nitrogen, phosphorus, and potassium. Follow the instructions on the pack for feeding quantity and regularity.

Pruning your Tomatoes

The good news with growing determinate tomatoes is that they don’t require a lot of pruning. All you should really do is trim away some of the bottom leaves, as these are taking away the energy that the plant needs to flower and produce fruit.

If you do happen to grow some indeterminate tomatoes, then these will need regular trimming and pinching out of lateral growth. The idea is to only have one main stem along which the fruits are produced.

This is a task that needs to be carried out every couple of days or so because these lateral branches will grow amazingly quickly. Lateral stems are those that grow from the main stem at the point where the leaves attach to the stem.

When these are quite small, they can just be pinched off using your thumb and forefinger. However, once they get a little thicker, you’ll have to use a pair of garden shears to remove them.

You also need to remove the lower leaves of indeterminate tomato plants so that the plant can put all of its energy into producing flowers and fruit.

Harvest your Tomatoes as they Ripen

Now that you’ve taken care of all the essential elements of growing tomatoes on your balcony, all that’s left to do is to harvest the ripe tomatoes. As soon as the tomatoes reach their final color, they’re ready to be harvested.

You can even harvest tomatoes that are not fully ripe as they will continue to ripen off the plant. You can place these on a warm windowsill indoors or even in the fruit bowl on your kitchen bench. Just remember to keep them at room temperature because they still need the warmth to ripen fully.