moderate · balcony
How to grow cherry tomato
The most rewarding thing you can grow in a pot, and the crop where the difference from shop-bought is most obvious.
Solanum lycopersicum · Solanaceae
Why bother
Commercial tomatoes are picked unripe to survive transport. A cherry tomato ripened on the plant is a different food, and a single plant can yield several kilograms.
What it needs
- Light
- 6-8 hours of direct sun. This is not negotiable — shade means no fruit.
- Water
- Deep, regular watering. Irregular watering is the direct cause of split fruit and blossom end rot.
- Soil
- Rich compost. From flowering onward, feed weekly with a high-potassium tomato feed.
- Temperature
- 18-27C. Fruit will not set reliably below 13C or above about 32C.
- Container
- Minimum 30cm pot, about 20 litres, per plant. Cramped roots cap the yield.
- Time to harvest
- 10-12 weeks from transplanting.
Step by step
Week 0
Sow indoors
Sow 5mm deep in small pots, somewhere around 20C. A windowsill is fine.
Week 3
Pot on
When the seedling has two true leaves, move it to a 9cm pot. Bury the stem deeper than before — tomatoes root along buried stem.
Week 6
Harden off
Before moving outside, put the plant out for a few hours a day for a week. Going straight out cold-shocks it.
Week 7
Plant into its final pot and support it
Move to a 30cm pot with a cane or string support. Cordon varieties need side shoots pinching out; bush varieties do not.
Week 9 onward
Feed weekly once flowering
Start high-potassium feed at first flower and keep watering consistent. This is the stage that decides your yield.
Week 12 onward
Harvest ripe
Pick when fully coloured and slightly soft. Leaving them on the plant an extra day or two is what produces the flavour.
What usually goes wrong
Dark sunken patch on the bottom of the fruit
Cause: Blossom end rot — a calcium uptake failure, almost always caused by inconsistent watering rather than a lack of calcium in the soil.
Fix: Water regularly and evenly. Mulch the surface to slow drying. Affected fruit will not recover but later fruit will be fine.
Lots of leaf, no flowers
Cause: Too much nitrogen, usually from general-purpose feed.
Fix: Switch to a high-potassium tomato feed once the first flowers appear.
Leaves curling upward
Cause: Heat stress or, less often, over-enthusiastic side-shoot removal.
Fix: Provide afternoon shade in a heatwave. Mild curl alone does not harm the crop.
Grows well beside
Basil, Marigold
Before you eat anything you grow: be certain of the identification. This guide describes cherry tomato specifically — it is not a way to confirm that an unknown plant is safe. Never eat a plant on the strength of an app alone.