Is it OK to use plastic zip ties to fasten the sechach (סכך) to the wooden beams to prevent the sechach from flying off in the wind?
Yes
Can you use them to tie up the lulav?
Is it OK to use plastic zip ties to fasten the sechach (סכך) to the wooden beams to prevent the sechach from flying off in the wind?
Yes
Can you use them to tie up the lulav?