Dear Orchid Doc,

Help! The leaves of my orchids are turning yellow and dropping off; some are even devoid of leaves. I spray with an insecticide every two weeks.

Sandy

Dear Sandy,

Yellowing of leaves can be very tricky to diagnose. In some cases it could be the result of fungus. You’ve made mention of using an insecticide but have made no mention of fungicide. On the other hand, it could be too much or too little water. How does one know the difference between death from too little water or from too much water? When the orchid is getting too much water, the leaves are yellow and show signs of rot. When there is insufficient water, they will wrinkle and dry before they die.

Dear Orchid Doc,

When my orchid roots are dry, especially the ones in stones, is there anything I can do to revive them or to jump-start new roots?

Michael Anthony

Dear Michael Anthony,

Use a bypass pruner to cut the roots at the end of the green part, where the dry part begins. Bypass pruners have two blades “passing by” each other to make the cut. At least one of the blades will be curved: a convex upper blade with either a concave or straight lower one. Water and fertilise as usual, as this will encourage new growth.