How to Ripen Green Tomatoes (UK Guide)

Every UK gardener eventually faces the same situation — autumn arrives and your plants are still covered in green tomatoes. Cooler temperatures slow ripening dramatically, but the good news is most tomatoes can still be saved.

This guide explains how to ripen green tomatoes successfully in the UK, both on and off the plant.

For the full tomato growing system, see TOMATOES: HOW TO GROW, BEST VARIETIES, PROBLEMS & EXPERT TIPS (UK GUIDE).

Why Tomatoes Stop Ripening

Tomatoes need:

• Warmth
• Light
• Stable temperatures

Below about 10°C, ripening slows significantly.
Below 8°C, it often stops completely.

This is why UK crops stall in September and October.

Step 1: Help Them Ripen on the Plant

Before picking, encourage natural ripening.

Do the following:

• Remove new flowers
• Remove small new fruit
• Reduce watering slightly
• Remove shading leaves
• Improve sunlight exposure

This helps the plant focus on existing fruit.

Step 2: Lift Whole Plants (Very Effective)

A traditional allotment method:

1. Pull up the whole plant
2. Hang upside down in a shed or garage
3. Keep frost-free

The plant continues feeding fruit while dying back slowly.

This often ripens tomatoes surprisingly well.

Step 3: Ripen Tomatoes Indoors

Pick fruit when:

• Full size
• Glossy green
• Slightly lighter colour

Do not wait for frost.

Paper Bag Method

• Place tomatoes in a paper bag
• Add a banana or apple
• Store at room temperature

These fruits release ethylene gas, which triggers ripening.

Windowsill Ripening

Works for:

• Partially ripe fruit

Avoid direct cold windows.
Too much sun can soften fruit unevenly.

Box Method (Best for Large Harvests)

• Lay tomatoes in a single layer in a box
• Keep dry
• Store around 18–20°C
• Check weekly

Remove any rotting fruit immediately.

Can All Green Tomatoes Ripen?

They must be mature first.

Good candidates:

• Full size
• Slightly pale green
• Glossy skin

Poor candidates:

• Very small fruit
• Hard dark green fruit

What If They Still Won’t Ripen?

You can still use them:

• Green tomato chutney
• Fried green tomatoes
• Pickling

Nothing needs to be wasted.

Final Thoughts

In the UK, green tomatoes at the end of the season are normal. With the right methods, most fruit can still ripen and be enjoyed rather than lost to cold weather.

Return to TOMATOES: HOW TO GROW, BEST VARIETIES, PROBLEMS & EXPERT TIPS (UK GUIDE) for complete tomato guidance.