A Gardeners Forum Forums General Discussion Plant pests and problems Oh, No! What have I done?

I decided to try one more time to grow gardenias here in Desert Southern California. Armed with knowledge from previous failed attempts, I decided to try rolling pots so I could shade them from the sun most of the hottest days, and control the soil and nutrients for the acidity they like). I planted two in different pots and all was going so well, then I tried neem oil to protect against pests. I used the oil mixed per instructions, on the gardenias, my rose bushes, and my veggie garden. One gardenia wilted a bit and had brown leaves, but is coming back with new growth. One has no leaves (except the dead ones I picked off) but has green stem at the roots. It was the smaller of the two plants. One rose bush also looked like it was dead, but is sending up new growth. The other roses are unharmed, as were the edibles. What did I do wrong? It may have been too late in the day? I should have done it in the evening or early morning? Does anyone know the safety precautions for using it?

Also, will the one gardenia come back? Or should I give it a respectful funeral and replace it? Thanks for any help you can give.

I've never used neem oil but I can tell you that if you see green growth then it's still living. I'd cut away the dead growth and wait patiently.

Neem oil, if mixed correctly (2oz per gallon or so is what I think most manufacturer's recommend) should not hurt your plants, although if you spray it on in bright sunlight it will cause the plants to toast. The nice slick coating amplifies the sunlight and it will burn the whole leave right off. I think they recommend spraying it on in the early morning or late evening where you don't have the possibility of frying your plant.

Also, Neem will not work as well as the heavy-duty chemical pest killers, so you will have to use it repeatedly (a few times to once a week) as it doesn't kill eggs and "wears" off after a few days.