I wouldn't. Many trees have allelopathic properties.

I wouldn't. Many trees have allelopathic properties.

If not fully composted leaves contain a lot of tannins and phenols which can do more harm than good to a wide variety of plants...especially in a soaked "tea" concentrate.

You would get some of the nutrients that the tree leaves have and it would be better to use that "tea" in the garden then dumping it down the sewer. If there are growing plants try a little of the "tea first before spraying the whole plant, but spraying over barren ground some time before seeding most likely will have little affect since the allelopathic properties the leaves might have (not seen when the leaves are used as mulch) do not last very long.

Thanks for the replies. When I first noticed the tea, I did put a little on a couple plants. They are still alive and that's all that matters, for the time being. Will monitor them to see if they become stunted. I really doubt that will happen though. Really light and didn't put too much on them.

By the way, how often are spinach plants supposed to be watered? It's getting much cooler outside so the water isn't evaporating as fast. I'm growing in pots.

Is the soil supposed to be really moist at all times or should they be allowed to "starve" , then watered.

So much conflicting info on this on this watering issue.

Would oak leaf tea help acid lovers? Or at least not hurt to use to water them other than throw out?

Oak leaf tea would have no more help for acid lovers then would Oak leaves. Oak leaves, pine needles, etc. do not significantly affect soil pH. To lower a soils pH you need something that will add more free Hydrogen ions, sulfur.
How often to water Spinach now depends on how fast your soil drains, how quickly the plants transpire the moisture the soil has (affected by temperature as well as wind), and if the soil is well mulched or not. Keep an eye on them since you do not want them wilting.