Question
I have two questions.  First, after much searching i have finally found a supply of pine needles for over wintering my container plants.  My question is; in your ebook you say 6 inches of mulch, Since I am winterizing container plants and have too many to store in my garage or similar place, is that 6 inches above the top of the soil?  I have 6, 12" pots to winterize plus a couple of flats worth or smaller pots that I am trying to figure a way of doing it.  Also i was going to put a layer of burlap or similar sheeting over all of them and I wasn't sure if i should or not.  And I didn't know whether or not to put the sheeting down first with mulch over it, or vise versa.  
Second question is as far as fungicides go, i am using neem oil.  How much should i really apply if i can't reapply during the winter (if its too harsh of a winter).  And if neem isnt the way to go, what's another good alternative.  And just so you know i live in zone 5 (northern Indiana).  Thanks

Answer
Hi TIm,

Given your location, use about 6-10 inches of mulch.  That layer needs to be from the soil line and the sides of the pots.  Some growers build a wooden frame around their plants to hold the mulch together.  They then disassemble the frame in spring.  

Prior to adding the mulch, cut off any leaves that are taller than 4 inches, especially those leaves that will stick out of the mulch layer. Also spray the soil and plants with your fungicide.  Neem oil is fine. Use a generous amount. The main goal is to kill any fungal spores initially.  When the temperature drops below freezing, fungus is rarely an issue.  As always, follow the directions on the bottle.

With the burlap, my preference is to use it over the mulch to keep the mulch in place.  You'll see the benefit of this when the winds kick up.  However, some growers have also used burlap underneath the mulch.  The benefit of this is to make it easy to remove the mulch in spring.  There are two concerns about this method.  First, the burlap needs to be brand new.  If the burlap is already used, then there is a high risk of fungal spores in the burlap.  So if you have old potato sacks, avoid using them.  Second, you'll need to make sure that all the nooks and crannies are filled in.  You want to make sure that you reduce as much empty space between the burlap and plants as possible.

That's pretty much to it.  We have customers in other zone 5 climates who have successfully overwintered their plants, both in in-ground bog gardens and in containers.  The main goal is to reduce rapid temperature swings and prevent dehydration from freezing wind.

Good growing!
Jacob Farin