> ## Documentation Index
> Fetch the complete documentation index at: https://badixth-dc85e378.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Diagnose and Respond to Sunburn in Pineapple

> Identify sunburn in pineapple from bleached leaf tissue and sun-scalded fruit shoulders on exposed rows, and reduce damage with fruit covering, shading, and row orientation.

Sunburn damages both leaves and fruit on pineapple when high radiation combines with drought, low humidity, or reduced canopy cover. Fruit sunburn is the yield-critical form: it downgrades fresh-market fruit and creates entry points for rots. Sunburn is not a disease but is often mistaken for one.

**Regional priority:** High on exposed sites, thin canopies, ratoon blocks (uneven cover), and any block with fruit exposed to direct afternoon sun.

## When pineapple is most vulnerable

Most damaging during **fruit development and ripening (months 14 to 22)**, especially the west-facing rows and outer rows. Also affects immature plants during establishment on BRIS or open sites.

## How sunburn shows in satellite data

* Not directly detectable at Sentinel scale in most cases; damage is on individual fruit shoulders.
* On drone or very-high-resolution imagery, bleached leaves show as brighter reflectance on west-facing rows.
* **Indirect indicator**: sustained high solar radiation + low NDWI over the block during fruit development is a sunburn risk signal.
* Confirm on the ground.

## Field symptoms

* **Bleached, papery patches** on leaves exposed to the sun (west or south side)
* **Sun-scalded fruit shoulders** - the upper, sun-facing side of the fruit turns pale, then brown, then leathery
* **Cracked fruit skin** on the scalded area, often followed by [black rot](/guides/Crop/Pineapple/biotic/diseases/black-rot)
* **Corky, tough flesh** below the scalded skin
* Damage concentrated on **west-facing rows and outer rows**

## Reduce the damage by

* **Cover fruit with dried leaves** tied over the fruit shoulders (traditional method, effective and cheap).
* **Use paper or fabric fruit covers** on export-quality MD2 and Josapine.
* **Plant rows north-south** where possible; east-west rows expose fruit to direct afternoon sun.
* **Maintain full canopy** - avoid excessive N late in the cycle that causes older leaves to lean out and expose fruit.
* **Kaolin-clay spray** on fruit shoulders reduces radiation load on high-value blocks.
* **Time forcing** so fruit development avoids the hottest, driest weeks of the year where possible.
* **Irrigate during heat spells** - well-watered plants transpire and cool the fruit; dry plants overheat.

## Set an alert for early warning

<Tip>
  Turn the diagnosis into a trigger. Sunburn risk correlates with radiation and evaporation, not NDVI, so use weather and canopy-cover signals.
</Tip>

Recommended settings for sunburn on pineapple:

* **Weather alert** - 3 or more consecutive days with maximum air temperature above 34 C and solar radiation above 25 MJ/m2/day during fruit development.
* **Canopy-cover alert** - trigger on blocks with NDVI below the mid-fruit-development baseline (indicates exposed fruit).
* **Fruit-cover reminder** - schedule a walk-through 2 weeks after forcing to install fruit covers on all west-facing rows.

## Related

* [Pineapple Diagnosis](/guides/Crop/Pineapple/pineapple-diagnosis)
* [Drought](/guides/Crop/Pineapple/abiotic/drought) - drought raises sunburn risk.
* [Black rot](/guides/Crop/Pineapple/biotic/diseases/black-rot) - often follows sunburn cracks.
* [Set up automated crop alerts](/guides/alerts-notifications)