The bought basil is getting blighty-looking spots on some leaves (not downy mildew)

Just a few leaves affected so far, otherwise the basil plants look good still.

Haven't seen any of these spots on my home-started basil (Prospera) yet.

No sign of downy mildew on any of the basils yet.

Removed the north bed basils due to downy mildew

I do think there was home for some of them as new growth was appearing, but, overall the bed looked just gross and I didn't want to look at it anymore.  Left one plant just because.  Will plant buckwheat there soon.

Basil continues to die due to downy mildew, even the central bed and pots :((((

Yeah I don't think there's any hope for any of the basil.

However, I'm still holding out a teeny tiny sliver for some of the plants in the main basil bed which still have some pure, untouched new leaf clusters...  

Last basil harvest before downy mildew completely destroys everything?

Harvested from the few central bed basil plants which I can see the downy mildew is now taking these ones down too (despite having applied horsetail fungicide several times).  Froze most of this harvest (didn't rinse or anything), hoping I can use it for the two zucchinis that will be ready within a few days.

The main basil patch in the north bed is essentially totally kaput and nothing there looks appealing to harvest.  I haven't pulled them yet, just to see if by chance they might bounce back some how.

Sprayed the central and potted basils with horsetail fungicide again (to try to curb downy mildew)

^^^

Oh no! Downy mildew destroying basil!!!

Wow, just a week ago I had a great basil harvest and the plants looked fine.  Then a day or two ago I noticed the main basil patch was looking off.  I offhandedly thought maybe there had been some cool nights.  Today I went to do a good harvest and decided to look into what's going on.  Clearly it's downy mildew:  the underside of the leaves have the brownish powdery spores, and the tops of some leaves are yellowing / turning brown / dying.  Some leaves fell right off as I harvested (particularly the purple basil).

On the down side the crop is probably doomed; on the plus side it sounds like it's host-specific, so won't spread to other types of plants, and it doesn't live in the soil nor over-winter.

The handful of basil plants in the central bed also has it, now that I closely inspected it (at first I thought those were fine) -- I removed the affected leaves, will spray them with horsetail fungicide tomorrow once batch #2 is ready, and hope or the best.

Some resources:

https://extension.umn.edu/diseases/basil-downy-mildew

https://www.hobbyfarms.com/basil-downy-mildew-big-trouble-garden/