Which is why I don't allow my gardeners to spray anything anywhere.

I told him not to spray at all, but he said that he forgot...

As long as he did not saturate the the soil, you should be ok.

time for a new Gardner.

There is no way he is going to tell me that he saturated the soil. He probably did it! I do not think we can eat the plums when they come out!

Really that will all depend on what he used. If it's not a systemic weed killer and it did not get onto the leaves of the plum, the fruit will probably be fine.

If he used systemic weed killer then the plum tree may be damaged.

You should really find out specifically what he used. The brand name too.

Find out what it was and then ask on the fruit tree forum what to do next.