Your bulbs store a lot of energy so if you had reasonably sized hybrid bulbs to begin with they can survive one season of stress and come back next year, if a bit diminished. (They lost energy making leaves that were killed before they could photosynthesize long enough to build the bulb back up.)

To be honest the organic antifungals (basically suspensions of sulfur) don't work particularly well and Botrytis is hard to stop.

So it depends on how much you like your lilies vs. how organic you want to be.

Myself, I try to avoid chemicals as much as possible. I don't react to every little spot and blemish by whipping out the "heavy artillery". But, I have some native lilies that are particularly susceptible to botrytis (and that are young with rather small bulbs) and I will spray them at the first tiniest sign of Botrytis.

I've seen entire beds of my mature hybrid lilies look like they'd been flamed with a blow torch. Those could survive being depleted one season and come back the next.

On the other hand, I had an area with 5 pardalinium that got Botrytis one season. The next season only one much diminished plant came up that didn't bloom. This year that one bulb is looking strong. So I lost 4 out of 5 and the fifth took 2 years to recover.

If you are firmly opposed to chemicals you'll want to do several things to not have problems in the future,

1)choose lily varieties known to be botrytis resistant, 2)strip this bed of the first couple inches of compost and soil and replace, 3)be careful not to spray water on the plants when you water them (though you can't do anything about the rain), 4)plant your lilies with plenty of room between them, and 5)be absolutely scrupulous about Fall clean-up of your beds.

If you choose to use chemicals I use any of the anti fungal (only) rose sprays. I don't use the combined anti-fungal insecticide rose sprays. I don't think they work as well and I want to use only the chemicals that I need (for as limited of a time as possible).

-Helen

In addition to the other cultural suggestions that Helen made, I'd like to add 1) increasing air circulation keeps disease problems down and 2) water in the morning so that the foliage has time to dry off before nightfall.

Can I permit them to bloom and then cut off the diseased foliage or should I not let them bloom to save the bulb?
This is weird, my Asiatics and tiger lilies are budding now, but these diseased Casa Blancas are right behind them - they are way early for me. I moved 2 of the biggest strongest diseased ones to a location with good drainage, sun, air - hasn't stopped the onset of the disease tho. I have a couple packs of Messenger which i think I will spray on all of them to see if it can help them shake it.

Blooming and leaf production both deplete the bulb, but leaves pay that back, and then some, through photosynthesis. Your bulbs already used up energy to produce leaves. If most of the leaves are gone then the bulb didn't get the "payback" and has already been depleted to an extent. Then, the safest thing is to remove the buds so your bulb isn't further depleted. If only a few leaves were affected and you still have a number of green leaves on the plant, you are probably fine. But you will need to treat the plant to keep it from affecting the remaining good foliage.

Moving already contaminated bulbs won't stop the disease - you have to kill the fungus that is on them already. Though being in a better location may help with next year.

Also, are you sure you have Botrytis? If so, the problem usually starts from the bottom of the plant (since the fungus is splashed up from contaminated soil) and works its way up. And the affected leaves will completely shrivel up, leaving a "Dr. Seus - like" plant with a tuft of green at the top and bare stalk below. (That is, if the plant isn't completely overtaken). It also affects leaves at any stage of development. Blackened edges as leaves unfurl sounds like it might be something else.

-Helen

Here is a link that might be useful: Botrytis Link

Thanks Helen that was very informative. It is not botrytis then - doesn't look like that at all. The top leaves are slightly curled, and look like they are sun burned, then they turn brown or black. I have had this thing spread thru my whole garden. I have 45 azaleas and rhodos and had to prune them very hard 2 yrs in a row to removed the diseased leaves and this yr first time they are virtually free of it. Up till now I had kept the lily bed free of it. Has really taught me to balance the organic natural gardening method of letting leaves lie vs cleaning beds thoroughly. I have a lot of gardens so I utilize both methods depending. Thanks again!
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