How to treat "yellowing disease" of flowers and trees?

Based on " south acid and north alkali for Chinese soil, when garden plant originated from the south are transplanted to the north, they are often applied ferrous sulfate (also called iron fertilizer which is a indispensable element of these plants), especially for cycas and other acid plants. Ferrous sulphate could adjust soil PH and promote chlorophyll formation, so it can treat "yellowing disease" caused by iron deficiency.

The symptoms: At the beginning, mesophyll become yellow, the leaves sides, middle or tip appear brown spots on young leaves; Times later, leaves fall off.

Usage:
1, mix 10g ferrous sulfate with water 2~2.5kg for foliar spraying.

2, foliar spray 1 ~ 2 times a month in the normal growing season.

3, in disease period, 10 ~ 15 days a time , 2 ~ 3 times in succession.

The plants that’re suitable to apply ferrous sulfate for "yellowing disease” are: all kinds of xi acid plants, such as cycas, azalea, camellia, milan, bracketplant, asparagus, Hester prynne, poinsettia, five needle cypress, jasmine, ferns, palm and various kinds of flowers and trees bonsai.