Hi guys,

I've already boxed my zone 9 palms here in NJ, but then warm weather unexpectedly has come and now the average temperature is >10C/50F. My boxes dont't have transparent roofs and the only thing I can do is open sides. But do I need to do this? Or they are fine being closed in such warmer weather?

You should have held off as long as possible before boxing/wrapping up your palms. Like you obviously don’t want to leave it too late, but you don’t want to jump the gun early either. Ideally they won’t be wrapped up properly before December arrives, since they need the airflow and sunshine. You might get away with having them wrapped up for 3 months from December - February, but not for 5 months! The lack of sun and airflow will cause problems with the crown.

If there is no frost forecast, don’t even think about wrapping them up. And if it was only a minor nighttime air frost a few weeks back, you only needed a little makeshift cover that can easily be removed again, before the proper secure wrapping/boxing in early December. No point wrapping things up in say October. And if you have to protect things in October (sounds like you don’t) there is no point growing those things in  the first place in such a marginal climate. Even the people growing CIDP and Washies in Poland don’t put the boxes and covers on until mid-November at least.

I'd open any enclosures at any opportunity of milder weather. These structures are really there for the extremes that might damage or kill your palm(s). What types of palms are you protecting and how?

2 hours ago, Las Palmas Norte said:

I'd open any enclosures at any opportunity of milder weather. These structures are really there for the extremes that might damage or kill your palm(s). What types of palms are you protecting and how?

Agree 100%

11 hours ago, UK_Palms said:

You should have held off as long as possible before boxing/wrapping up your palms. Like you obviously don’t want to leave it too late, but you don’t want to jump the gun early either. Ideally they won’t be wrapped up properly before December arrives, since they need the airflow and sunshine. You might get away with having them wrapped up for 3 months from December - February, but not for 5 months! The lack of sun and airflow will cause problems with the crown.

If there is no frost forecast, don’t even think about wrapping them up. And if it was only a minor nighttime air frost a few weeks back, you only needed a little makeshift cover that can easily be removed again, before the proper secure wrapping/boxing in early December. No point wrapping things up in say October. And if you have to protect things in October (sounds like you don’t) there is no point growing those things in  the first place in such a marginal climate. Even the people growing CIDP and Washies in Poland don’t put the boxes and covers on until mid-November at least.

Thank you. We had very cold October, the whole month forecast had low temperatures and a couple of nights with freezing temperatures, so I boxed my 2 zone 9 palms (Pygmy Date Palmn & Mexican Fan Palm), the rest are still unboxed.

To be fair, my last year, all my palms did very well, boxed for 5 months.

6 hours ago, Las Palmas Norte said:

I'd open any enclosures at any opportunity of milder weather. These structures are really there for the extremes that might damage or kill your palm(s). What types of palms are you protecting and how?

Thank you. I boxed only 2 zone 9 palms for now  (Pygmy Date Palmn & Mexican Fan Palm).

31 minutes ago, PashkaTLT said:

... To be fair, my last year, all my palms did very well, boxed for 5 months.

I know that in my climate (PNW wet, chilly winters) keeping these enclosures ventilated is advantageous for reducing mold and mildew. So, it would seem you've found success "last year". Continue with what works for you. Protection methods and variations aren't really an across the board solution.