Hey Ross, Are your two Haraellas with wildly differing root sizes the same age and parentage? The older the orchid, the bigger the roots and leaves would be.
Genetics plays a role here to be sure. Different orchids employ a variety of strategies for water uptake and storage. Phalaenopsis definately use their roots, and their thick leaves for water storage. Orchids rather uniquely use all portions of the plant (except the flower!)for water storage. So mass is storage whether its leaf, root or swollen stem (pseudobulb) does not really matter; it's a water savings account if you're an orchid. The larger the proportional mass of the plant, the more able it is to survive a drought.
|