Heat, Erratic Rain and Water Stress Squeeze India's Tomato Crop

Heat arriving at the wrong stage

India's tomato crop is under pressure from a combination of high temperatures, erratic rainfall and water stress, according to reporting by India Today Science in its Climate On My Plate segment and by Aaj Tak. The core issue identified by researchers is not a warmer average season but extreme weather landing at the wrong point in the growth cycle: tomato requires specific temperature, rainfall and water conditions at each distinct stage, and shifting weather is delivering heat or rain precisely when the plant can least absorb it.

Flowering and fruit set are the most exposed phases. Aaj Tak, citing research by the ICAR-Indian Institute of Vegetable Research, reported that prolonged high temperatures affect flower development and pollen quality, which feeds directly into weak fruit set and lower final yields. In one field study, tomato varieties grown at average daytime temperatures of 38.4 degrees Celsius showed clear effects on flowering and yield-related traits.

A 2026 study examined 76 tomato varieties grown through the summer season in Punjab and found that temperatures above 35 degrees Celsius can be damaging to yield, with effects running from plant growth through to fruit formation. NewsBytes reported the same 35-degree threshold as the level at which flowering and growth begin to break down. For a grower, a heatwave at flowering is not a line on a meteorological chart but fewer fruits and a smaller harvest.

Too much water is also a loss

Excess moisture is the mirror image of the problem. Heavy or badly timed rain damages plants, raises disease pressure and complicates harvesting — a serious constraint for a crop that is highly perishable and cannot be left standing in the field until conditions improve.

The most concrete figure in the current reporting comes from Mizoram. An ICAR report cited by both Aaj Tak and NewsBytes found that open-field tomato cultivation during the pre-kharif and kharif seasons, under heavy rainfall and fluctuating temperatures, saw yields fall by around 70%. Cultivation under controlled or protected conditions produced substantially higher yields under the same weather.

The breeding response

A 2025 study on the effect of heat across tomato varieties found that high temperatures can sharply reduce yield, root development and the plant's photosynthetic capacity. The damage was not uniform: some varieties tolerated heat better than others, which is why breeding programmes are now focused on lines that hold yield under high temperatures.

That work is progressing. A study published in August 2026, involving researchers including from the ICAR-Indian Institute of Vegetable Research, identified tomato varieties carrying traits associated with better heat tolerance — material that can be used to develop new high-temperature varieties. A separate 2025 study modelled tomato cultivation in central India under future climate conditions and found that rising temperatures may somewhat accelerate flowering and fruiting while still reducing yields, with changing rainfall patterns affecting production differently from region to region.

Supply and price implications

Because tomato is perishable and is grown across multiple regions and seasons, weather damage in a major producing belt can quickly thin market supply and push prices higher. Some Indian plains already run summer temperatures that make tomato cultivation difficult, forcing production into other regions or other seasons; climate change has not removed those long-standing constraints but added another layer of pressure on top of them.

Aaj Tak cautioned against attributing every tomato price spike to climate change. Crop cycles, planted area, pests and disease, transport, storage and general market conditions all shape the price. What climate change adds is additional uncertainty in an already sensitive crop: tomatoes are not about to disappear from Indian kitchens, but some seasons will become harder to grow through.