Sometimes, we work for days and weeks on our tomato plants. The plants get loaded with lots of fruit, but then we face this one problem: They remain stubbornly green—day after day—and the tomato does not ripen.

If your tomatoes are also refusing to ripen, you are not alone.

Many gardeners face this frustrating issue. They keep on thinking, "Why are my tomatoes not ripening? It's incredible late in the growing season." However, there are some clear reasons for this and solutions for common issues.

So, here are some reasons why your tomatoes are not turning red (or yellow, orange, or whatever their final colour should be) and what you can do about it.

Three essential factors impact tomato ripening: temperature, ethylene gas, and plant genetics.

This is a natural plant hormone that triggers ripening. It also softens the fruit and changes its colour.

These pigments give tomatoes their red, yellow, or orange colour.

The best temperature for ripening tomatoes is between 68°F and 77°F (20°C - 25°C).

If something interferes with these factors, your tomatoes will stay green and not ripen correctly.

Tomatoes shut down ripening when temperatures go outside their comfort zone. This means when it is too cold or too hot.

Too Hot (above 85°F / 29°C during the day or 70°F / 21°C at night) – Heat stops lycopene and carotenoid production, keeping tomatoes green.

Too Cold (below 50°F / 10°C) – Growth slows, and ripening is delayed.

How to Fix Temperature for Tomato Ripening?

For Heat:

Provide shade using row covers, shade cloth, or nearby taller plants.

For Cold:

Harvest mature green tomatoes before frost and ripen them indoors (more on that later).

Tomatoes need ethylene to ripen. This is a natural gas. But some conditions slow its production.

How Can You Provide Ethylene Gas for Ripening Tomatoes

Prune excess Foliage to allow air circulation.

Encourage ripening with bananas or apples – These fruits emit ethylene gas, so place them near tomatoes in a paper bag.

This is often called overfeeding. You may have too much nitrogen if your tomato plants are big, lush, and full of leaves, but your fruit won't ripen.

How to Fix Nitrogen Problem In Tomatoes?

You should stop fertilizing your crops with high-nitrogen fertilizers (like general-purpose plant food).

Use a low-nitrogen, high-phosphorus fertilizer (like bone meal or tomato-specific food).

Thick leaves and branches can block sunlight and restrict air circulation, preventing tomatoes from ripening evenly.

How to Fix the Overcrowding Problem In Tomatoes?

You should trim excess leaves, especially those shading fruit.

Always space the plants 18-24 inches apart to improve airflow.

Don't remove all leaves—tomatoes still need shade to prevent sunscald.

Some tomato varieties naturally take longer to ripen. This is especially true for the larger ones like Beefsteak or Brandywine tomatoes.

Tips for Ripening Tomatoes Red:

Choose early-ripening varieties if you live in a short growing season area.

Be patient! Some tomatoes take 80+ days to mature.

If you pick tomatoes before they reach maturity, they may struggle to ripen fully. You should always wait until they reach the breaker stage (when they start showing colour) before picking them.

Once tomatoes start changing colour, they will continue ripening off the vine.

Certain diseases, like blossom-end rot or tomato blight, can delay or stop ripening. Pests like aphids and whiteflies are also Stressed plants.

How to Deal with Disease and Pest Damage in Tomatoes?

Remove infected leaves and use natural pest control (like neem oil or insecticidal soap).

Keep plants well-spaced and avoid overhead watering to reduce disease risk.

If cold weather is approaching or your tomatoes won't turn red, bring them inside to force ripening.

Paper Bags – Place tomatoes in a bag. Do it with a banana or apple (ethylene gas speeds ripening).

Cardboard Box Method – You can lay tomatoes in a single layer in a warm, dark place.

Window Sill Trick – If tomatoes have started to turn, place them on a sunny windowsill.

You should always avoid putting green tomatoes in the fridge! The cold temperatures stop ripening and ruin flavour.

If your tomatoes are staying green, there is no need to panic. It is a problem that can be solved. Just use our tips and ideas for making your tomatoes red, and you will never again wonder why your tomatoes are not ripening.

With a few adjustments, you can get those stubborn tomatoes to ripen and enjoy the harvest you have been waiting for!