My Oleanders Have Yellow Aphids After Being In The Basement All Southern Ontario Winter. I Sprayed Them With A Mixture Of Water,

Question

vinegar and Dawn. Now, I am worried I have killed the plants. I can still see the aphids moving and there is sticky substance on the outside of the container. I fear for the worst and have them outside on a sunny day in March for Southern Ontario. Will they die? Or thrive till May 24 – our general day for putting plants into the ground?

Answer 1

If just one of those things were to have happened, I would give it a better chance. With damage compounded on top of an infestation, I would be concerned that the plant may not recover. Add bright sunlight to the stress, and it may be on its way out.

You will want to remove any dead material, first. Trim back any branches that are completely dead and brittle. Leave any with some bend, or life, to them.

Treat the plant with a light spray of neem oil. This will be enough to get rid of aphids, usually. If that does not control them, then there are many other organic options that need to be used in moderation, still.

These articles will help:

https://www.gardeningknowhow.com/special/organic/what-are-organic-pesticides.htm

https://www.gardeningknowhow.com/special/organic/natural-home-pesticides-organic-garden-pest-control.htm

Put this in a sunny spot indoors. Water only when the soil is dry just out of your finger's reach, within the soil. This will keep from over-watering, which will help in the plant's recovery.

Here is an article that will help you to care for your Oleander while it is indoors, recovering, and during winter: https://www.gardeningknowhow.com/ornamental/shrubs/oleander/overwintering-oleander-indoors.htm