Hi, my neighbours are concerned about the yellowing of the leaves on their Magnolia Michelias. I read that too much sun could be the cause, but the tree's against the house and faces south. What would you advise? Debbie.

It is quite normal for yellowing to occur at this time of year coming from winter into spring. I see from the photo sent in they have put mulch around the base which is good. It is in the correct position being on the south side of the house under the eaves so it's unlikely to get frosted. Suggest mixing up Tui Epsom Salts (Magnesium Sulphate) in a watering can and applying to help green up the leaves.

Seasol plant tonic will also help with general plant health.

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