How do I change color of interactions based on interaction value using an ifelse() statement in an plotweb bipartite?

Hi I am having trouble trying to get ifelse statements to work in a normal plotweb used to color interaction based on the total quantity of interaction of each cell in the matrix. I had the same problem with the high bar colors, but since there were only a few and a straight vector, it was easy to manually code.

Here is the code I am using, I want to color interactions greater than 15 as dark turquoise and keep the rest as default grey (grey80).

I have tried many different statements but I cant seem how to figure out what to put in the [,] to signify for the function to go through every individual cell and apply the statement instead of summing them, elem,elem also doesn't seem to work. Attached is a picture of the function's output currently

plotweb(LadyNet, 
        abuns.type='additional',
        arrow="up.center",
        text.rot=90,
        col.low=c("olivedrab3"),
        col.interaction =(ifelse(LadyNet[,] < 15,'grey80','darkturquoise')), 
        col.high = c("grey10","#FF0000","grey10","#FF0000","grey10","#FF0000","grey10","grey10","grey10"),
        high.lab.dis = 0,
        ybig=1.2,
        y.width.high = .06,
        high.spacing = 0.011, 
        y.lim = c(-1,2))