I live in Aotea, Porirua. There is a lot of clay and very little good soil but I have put in a lot of good soil to plant a row of Grisellia’s down the fence line approx.25 total. I lost approx.12 and have since replanted 2-3 months ago. Now I have about 4-5 plants with Brown spot on the leaf. Up until now they have been in very good shape (nice green colour leafs).

I have been concerned with the soil being too wet but with the extra soil I have put in and the heated dry weather I would have thought the soil would be pretty dry by now.

Can you help me please.

  • You must to post comments

Hi Jeff,

It looks to me like you may have die back or root rot with so many of the plants dying. It is a soil-borne fungus/pathogen that causes the roots to rot and prevents the plants from up taking nutrients and water. It is often caused by water stress such as the plant not being watered enough during the dry months or the drainage in the soil is poor.

The best thing to do is cut out all the dead material and remove it. Remove all the dead plants. Improving soil health is always beneficial for the plant. It will help add nutrition and microbes as well as hold water in the drier months and adding organic material will help improve poor drainage. I know you have stated you have put a lot of new soil in which is great. Gypsum can also help break down clay soils.

The products you can use to treat this problem are Buxus Blight Fighter, Buxus Blight Buster or Root Protect Aliette. Drench the soil and spray the foliage of the plant. You may need to do this over the span of a couple of months to ensure you get rid of the problem.

There is a product called Trichodermia which is a beneficial microbe you can also add to your soil.

The Palmers Team

  • You must to post comments
Showing 1 result
Your Answer
Guest Author
Post as a guest by filling out the fields below or if you already have an account.