A problem is spreading rapidly through my phrag collection.
(1) New growths start out green and healthy until they are about 4 - 5 inches tall and then they develop a sick yellow or yellow brown coloration and stop growing.
(2) Center new leaves of mature plants are developing areas having a light yellow coloration and then turn brown and the plant growth declines.
(3) Some leaves on mature plants and seedlings develop ugly black V shaped marks (both sides of leaves).
These problems do not appear on my paphs which grow in the same general area of the greenhouse. There is plenty of air movement and for years I have followed general cultural principles for phrags and have been quite successful. RO water, Ca/Mg supplements, etc - I never had any problems until recently. The problem appears to be spreading fast.
Are there any specific fungal or other issues that affect phrags (and not paphs) at such a fast rate? And how can the problem be treated?
Any help would be appreciated
Thanks
Chas
(1) New growths start out green and healthy until they are about 4 - 5 inches tall and then they develop a sick yellow or yellow brown coloration and stop growing.
(2) Center new leaves of mature plants are developing areas having a light yellow coloration and then turn brown and the plant growth declines.
(3) Some leaves on mature plants and seedlings develop ugly black V shaped marks (both sides of leaves).
These problems do not appear on my paphs which grow in the same general area of the greenhouse. There is plenty of air movement and for years I have followed general cultural principles for phrags and have been quite successful. RO water, Ca/Mg supplements, etc - I never had any problems until recently. The problem appears to be spreading fast.
Are there any specific fungal or other issues that affect phrags (and not paphs) at such a fast rate? And how can the problem be treated?
Any help would be appreciated
Thanks
Chas