Q.Skimmia ‘Rubella’
The leave on my Skimmia ‘Rubella’ are turning yellow. I understand that the soil needs to be more acidic. I have purchased extract of seaweed with sequestered iron, but it says on the instruction to use during the growing season.
1. When is this?
2. Will the plant suffer if it is not treated?

Certified GKH Gardening Expert
It's an evergreen, so actively grows year round, though any treatment or fertilizing is best performed in spring or summer. I would recommend pinpointing other possible reasons for the yellowing before treating, however, as it could be due to other factors. This article will help: https://www.gardeningknowhow.com/plant-problems/environmental/plant-leaves-turn-yellow.htm