Fwiw, we've been using Tebuconazole 3.6F Fungicide Offset Torque, whenever we see any sign of Rust. We've found it to be very effective against Rust and Leaf Streak. Had an outbreak last year. Ironically, the first year we opened. Talk about a double whammy; had to deal with Covid and Rust, all in our first year. At any rate, after doing some reading/research on different methods to combat Rust, we put together an action plan.
First, always water earlier in the day. The Rust spores thrive in moist and humid environments. Watering late in the day just encourages them.
Additionally, allow plenty of spacing between plants. Plants that are lumped together tightly have more difficulty drying out, thus, encouraging Rust.
Trim off any infected foliage, and dispose of in a sealed container. Even burning the cut foliage doesn't kill all the spores.
We use a spraying regimen of once every 3 weeks or so, depending on how much rain we've had late in the day.
Following those guidelines, and spraying with what I referred to above periodically, has helped us eradicate the Rust issue. That said, we remain diligent, as Rust spores can survive and remain inert until the right environment presents itself.
Jobe
