Calcium guide
Calcium is a secondary nutrient the crop needs to build strong cell walls, keep cell membranes healthy and grow new root and shoot tips. A...
Read the full guideCalcium deficiency symptoms crop by crop
How calcium disorders look in tomato, chilli, apple, mango, groundnut, potato, cabbage and pomegranate, and why they appear even on calcium-rich soils.
Calcium shortage shows in fruit and growing tips: blossom-end rot in tomato and chilli, bitter pit in apple, tip burn in cabbage, empty pods in groundnut and brown spots in potato tubers. These often appear on soils with plenty of calcium, because the plant cannot move calcium to the fruit when water supply is uneven or other nutrients crowd it out.
By Gafar Laiya and the Gujarat Bio Organics team. Updated November 2026.
Crop by crop
| Crop | What you see |
|---|---|
| Tomato, chilli and watermelon | Blossom-end rot: sunken dark patch at the flower end of the fruit. |
| Apple | Bitter pit: small brown spots under the skin, worse in storage. |
| Mango | Soft or spongy tissue near the stone in some varieties and poor shelf life. |
| Groundnut | Empty pods (pops) and poor kernel fill, because the pod takes calcium directly from the soil. |
| Potato | Internal brown spots and hollow heart in tubers, weak sprouts. |
| Cabbage and cauliflower | Tip burn of inner leaves and brown curd. |
| Pomegranate | Fruit cracking with irregular watering. |
Look-alikes
- Sunscald also damages fruit, but on the sunny side, not the flower end.
- Fruit borer damage leaves holes and frass.
- Boron shortage also causes cracking and corky fruit; test both.
When to look
- During fast fruit growth.
- After a dry spell followed by heavy watering.
- In humid, cloudy weeks.
Confirm and correct
- Confirm with a soil or leaf test before you spend.
- Read the full calcium guide for causes and correction.
- Use the symptom guide to compare with other nutrients.
Doses depend on the crop, soil and product, so this page gives methods, not amounts. Take the dose from your soil test report, the product label or your local agriculture officer or KVK. Results differ from farm to farm with soil, weather, crop and management. Farmer experiences on this site are their own reports, not a promise of results.
Read next
Blossom-end rot, bitter pit and tip burn: when the soil has enough calcium
Why calcium disorders appear on calcium-rich soils, why calcium sprays alone often fail, and how water, potash, magnesium and boron decide the result.
Read the full guideHow Gujarat Bio Organics can help
Since 2006, lakhs of farmers from Kashmir to Kanyakumari have used Immunity products on almost every crop: from the mango farms around Somnath to the apple orchards of Himachal Pradesh and Kashmir, the tea estates of Assam and Darjeeling, and the banana, coconut and cardamom farms of Tamil Nadu, Karnataka and Kerala. Each Special is one formula made for one crop and its common problems. Tell us your crop, soil test and what you see, and our team will tell you what to check, whether a micronutrient correction is needed, and which Special fits your programme.
- Vegetables guide and Immunity Vegetable Special
- Apple guide and Immunity Apple Special
- Mango guide and Immunity Mango Special
- Groundnut (Mungfali) guide and Immunity Mungfali (Groundnut) Special
- Potato guide and Immunity Potato Special
- Pomegranate guide and Immunity Pomegranate Special
Results differ from farm to farm with soil, weather, crop and management. Farmer experiences on this site are their own reports, not a promise of results.
Questions
What does calcium deficiency look like in tomato, chilli and watermelon?
Blossom-end rot: sunken dark patch at the flower end of the fruit.
What does calcium deficiency look like in apple?
Bitter pit: small brown spots under the skin, worse in storage.
What does calcium deficiency look like in mango?
Soft or spongy tissue near the stone in some varieties and poor shelf life.