We used a sheep’s fat product last year that worked very well. I don’t remember the name off hand, I’ll have to look it up and update this post. It was rainfast and the effects were noticeable for around a month after application. We sprayed a 60’ perimeter along woods and other problem areas and it worked. It’s an oil and can’t be applied with herbicides due to increased plant burn. It’s a clear, colorless, more or less odorless liquid.

For what it’s worth, Plantskyd is a joke imo.

Just looked the name of the product up, it's called Trico.

https://www.helenaagri.com/products/products/repellent/trico-pro/