Fungicides

[charlesf6]

Looking for an effective safe fungicide as my
bulbophyllum netted pot has attracted a lower level of green algae of some sort after almost daily wetting all summer, anyone used this or know of something else.

I'd really rather not repot as it seems to just recently established itself after a very long time.

Safer Brand 32 oz. Ready-to-Use Garden Fungicide-5450-6 - The Home Depot

[SaraJean]

I haven’t tried fungicides for algae but I know there are algaecides on the market. The only one I have tried using was a weak solution of physan 20 but there was no noticeable change on my orchids that already had established algae, like all of my bulbos growing in sphagnum moss, I read somewhere that it is more of a preventative. Although algae is unsightly, it is not particularly harmful. So, basically, I have given up trying to keep my bulbos algae free and simply learned to live with it. My environment is too hot and humid and I was fighting a losing battle against something that wasn’t actually causing any problems :/
If you place the net pot in a cache pot (I know this is not always possible with this wandering genus of orchids), it will cut out the light to the algae and die off. That won’t change the algae on the top portion of the media but it will take care of the sides, at least

By the way, when was the last time it was repotted?

[Dollythehun]

Amber Listerine sprayed on helps. I hate the looks too but also am trying to live with it.

[charlesf6]

Originally Posted by SaraJean

By the way, when was the last time it was repotted?

April changed from moss/bark to all moss.

[estación seca]

The algae is not a problem. Algacides by definition kill plants. Don't do that. Learn to live with the algae.

Bill Thoms writes his plants grow so fast he must repot every 2 years. My experience has been if they aren't growing rapidly I'm not watering enough.

[Ray]

1️⃣ Fungicides do not kill algae.

2️⃣ Algae is only an issue if it grows so extensively that it starts to suffocate the roots.

3️⃣ If you are getting a lot of algae growth, you are overfertilizing.

Semi-hydro pots are notorious for algae growth, but once I changed my feeding regimen to only apply 25 ppm N applied at every watering, it practically eliminated the issue.