Autumn still brings in the hearty cold bite now and again. These cold snaps are not ideal for your orchids and can bring on a few fungal diseases such as Erwinia, Crown/Root Rot, and leaf Blights.
Keeping prepared by preventatively spraying your orchids with Physan 20 will keep them healthy and disease free during the colder months.
Mix 1 teaspoon of Physan 20 to 1.8 litres of water and apply as a foliar spray fortnightly during Colder seasons.
To treat Orchid Rot (Erwinia):
Mix 1 Tablespoon of Physan 20 concentrate with 3.7 Litres of water in a bucket. Remove plant from potting medium and soak entire plant for 10 – 12 minutes. Cut away all rot with a treated tool.
(You can mix 1 teaspoon of Physan 20 concentrate in 0.9 Litres of water for a tool disinfecting solution)
Soak plant wounds again for another 10 minutes and repot in Physan 20 soaked compost.
For Orchid maintenance:
Mix 2 teaspoons of Physan 20 in 3.7 Litres of water. Spray anytime disease other than rot is evident. Spray once per month as preventative maintenance and be sure to soak potting medium when fungus is evident.
To treat botrytis:
Mix 1 teaspoon of Physan 20 per 11.3 Litres of water. During cool damp weather spray plants, flowers and under benches at first sign of the spotting on flowers. Normally weekly spraying will greatly reduce or eliminate the botrytis spotting.
Other Orchid diseases may require different mix ratios and directions, so check the Physan 20 bottle booklet for more treatments and instructions!