Today and tommorrow it will be raining.
It has been about 2 weeks since my last fungicide spray. (Decree)
It has been 7-10 days since my last calcium spray.
I have good color on Early Prestige.
We have 1 or 2 isolated instances of B/Edge Burn.
What would be the first course of action for me calcium or fungicide spray?

The Heritage label suggest the high rate 4oz/100 gal for boytritis
Is Heritage safe to use now on colored bracts and at that rate?

If I sprayed calcium or fungicide tommorrow 8-11am (rainy day) would it aggravate the situation or help it?

After spraying should I turn up the heaters to 70-72 for an hour or two to make sure the foilage will dry?

Thanks for your help!

tnt -

If you know that your environment can be conducive to botrytis than the fungicide application should be your first priority. Heritage is labeled at 4-8 oz /per 100 gallons has been tested for tolerance on poinsettias. The only problem is that you can't use any type of silicone based product with Heritage which means no spreader stickers or surfactants and spotting may occur. It is also best for suppression and doesn’t really over any type of prevention. If it has been 10 days since your last Decree application it would be OK to apply Decree again, Decree does work well for prevention.

Calcium and fungicide can't be avoided to prevent problems with bract edge burn and botrytis. The key is just to make applications as early in the day as possible, allowing foliage and bracts to dry as quickly as possible and definitely before nightfall. Make sure the plants are spaced adequately and provide horizontal airflow with fans - this will help the foliage dry faster. You can also heat the greenhouse and get the moisture evaporating up into the air. Follow the heating by venting with cooler, drier air. Repeat this several times throughout the day to keep the relative humidity down. If you can manage all this your calcium and fungicide sprays should not result in more problems with botrytis.

Ecke what would be the best fungicide to spray with at this point for prevention?

Would Cleary 3336 also work as a preventative/treatment in this scenario or would it lead to bract damage? Sorry to throw the thread slightly off topic, I just happen to have some on hand.

You would get major spotting with Cleary 3336. I would not recommend this. We have always used Decree every 2 weeks and calcium chloride every week.