I get asked a lot whether and how much to mulch gardens and landscaping. I actually have pretty strong opinions on the matter. Having maintained both mulched and unmulched gardens, I have become convinced that mulched gardens are far superior. Mulch serves to deter weeds and maintain moisture in the soil. A good mulch breaks down to compost over the season and feeds the soil.
That being said, how you mulch is very important. Here are a few things to consider:
1. Wait until soil temperatures are above 50 F. Otherwise you are trapping cold in the soil that slows plant growth. In New Hampshire that is usually early to mid may.
2. The type of mulch you use is important. I never use over-dyed mulch, either red or black, unless a customer insists. I try to find the darkest double ground mulch. Being double ground is important to ensure that the mulch does break down and not mat up.
3. How much mulch you put down matters. I have seen many landscape articles recommending up to four inches of mulch. I do not apply anywhere near that amount. Depending on the situation I usually find 1-2 inches is quite sufficient.
I also have some basic mulching rules (my crew loves me for this!)
1. The first is “Don’t let the mulch touch the plant material!” And never pile mulch around the base of a tree! You place-rake or toss the mulch between plants and shrubs, being careful not to let the mulch touch the base. My team knows I am going to check, especially the trees and peonies, both of which can suffer with mulch. (They also know I lift up the branches low to the ground and check under there…but thats between me and them. 😉 )
2. The second rule is “Don’t walk on the mulch!” Like painting the floor of a room, you have to have a plan, start from the back and work your way out, so you dont leave unsightly footprints and mat the mulch up. “Don’t walk on the mulch” is always a hard rule for new crew members, and it really becomes a sing song type of joke for us.
So what do you do with all that excess mulch at the end of the season?
At the end of the season, if there is mulch that hasn’t broken down I remove it from the garden. This can be done in early spring also. Sometimes larger pieces are all that’s left on the surface, and rather than mulching over that to just have it appear again in the fall, I remove it to compost in a longer-term composting situation.
So, mulch away, use double ground, not too much, and remember…. Don’t walk on the mulch!