Calcium Chloride vs. Chelated Calcium for Apple Fruit Quality and Size

Calcium Chloride vs. Chelated Calcium for Apple Fruit Quality and Size

A grower asks the difference between chelated calcium (CaEDTA) and calcium chloride for apple sprays, and whether calcium chloride reduces fruit size.

Calcium Chloride (CaCl₂)

• Most common, researched, and recommended foliar calcium for apples.
• Use food-grade only (not construction/de-icing grade).
• Apply from early fruit set until late August.
• Do not spray above 85°F (29°C)—risk of leaf/fruit burn.
• Stop 30 days before harvest.

Chelated Calcium (CaEDTA)

• Contains ethylenediaminetetraacetic acid (EDTA) to keep calcium soluble.
• Similar uptake, but studies show no advantage over calcium chloride for bitter pit prevention or fruit quality.
• More expensive.

Does Calcium Chloride Reduce Fruit Size?

No. Fruit size is primarily determined by:

1. Variety
2. Water availability
3. Crop load (thinning)
4. Tree health/nutrition

Calcium sprays improve firmness and reduce bitter pit—they don't shrink apples.

Best Practice

Use food-grade calcium chloride at labeled rates, timed correctly. It's the standard for a reason.