
PawPaw Education. The Image is how plants make cell walls of Fruits & Roots. Plants make up to 4 types of Pectin, and multiple Methyl-Ester-Pectin Polymers. Plus most important Calcium Pectate Polymers. And they interconnect the lipid layers & cellulose, to make the cell secure.
A Sulfur protein slime or precisely Cysteine-Rich Peptide Slime, lol.
This helps chelate things like Ferric Oxide, with is common in soils, and would be toxic with out this protective layer.
This created Iron Cysteine Ligand, with is able to safely pass though the lipid layers of the cell.
Calcium also make 8 of the Auxin transporters, needed for fruit & root growth.
Low levels of Calcium Pectate Polymer cause fruit cracking & problems like blossom end rot in some fruits.
These are some of the many reasons I frequently recommend:
Gypsum & Bone Meal. Calcium Sulfate & Calcium Phosphate.
Boron is needed at 2ppm to 4ppm in the soil for pawpaw to assimilate Calcium properly.
Boron also help with Gibberellins & insures all fruits of a cluster are the same size.
If yours are not, I recommend horse manure from horses feed ALFALFA.
Any questions, then ask.