http://forums2.gardenweb.com/forums/load/soil/msg0609100219981.html

Here is a link to the same question...you might find helpful. They say there that anytime is fine to mulch (by what I see...).

I have a question for YOU though about your raised beds...I just put in raised gardens (two weeks ago) and I wonder if you have noticed any changes in the "zone" of your plants with the raised beds? Someone told me that raised beds means you can plant something ONE zone higher (I am in zone 3 - could plant a 4??) - others say it remains the same.

Your input and experience with this?

Thanks :-)

Missti

Missti--in answer to your question. My raised beds are vegetable beds. My perennial beds are at ground level. I started raised bed gardening about 15 years ago mainly to try and escape the loss of several inches every year to invading grass. I love my raised beds, but as far as any zone difference I couldn't help you as the veggies are all annuals. I do find the beds warm up and thaw a little earlier than "in ground" beds. I also like them because you can plant more closely and thus get a bigger yield. As far as zones go,it's always fun to try things that aren't zoned for your area because even though you are a stated zone, many factors in your garden can affect your results. For example we live beside a river and often don't get frost when other areas near us do. Also protection from wind and good snow cover can make a big difference. So I say--try some zone 4 plants and see what happens. That's one of the joys of gardening.

Chickadee...Thank you for your input. I am going to try some Zone 4's and see if they make it through the winter. Just have to decide now what I want to try :-)

I thought of small raised garden for veggies as well - but not sure I could sqeeze much more into my small yard. Once the deck is finished I will see what room is left - maybe there will still be a perfect spot for another garden.

Happy Growing !

I have for many years had a goodly amount of mulch on my planting beds from late fall, when the tree leaves are abundant, through late summer and have not seen any problem with soil warm up in the spring. Neither here with my Lake Michigan beach sand soil, nor at daughters in southern Ohio where the soil is clay, not at sons on the east side of the state where his soil is also clay.
I have not seen a problem with soil warm up in the woods where Ma Nature plunks a lot of tree leaves on the soil where they stay all winter and on through the summer. She does not move that mulch to allow the soil to warm up, because that is really not needed.

There's a difference between leaving mulch on from the fall and putting mulch on in the spring. If you mulch in the fall, the soil doesn't get as cold during the winter, but if the soil is bare in the spring, putting mulch on while the soil is still cold will delay the warming of the soil.

I suppose you could get a slight jump on warming the soil by moving the mulch and letting the sun warm it, but it could backfire if you got some colder days after moving the mulch and I'm not sure it would help all that much even if you timed it exactly right.

So my approach would be to leave the mulch on if you put it on in the fall, but delay mulching if the soil is bare and you want to give it a chance to warm up.

Another note to misstiblue. These are two plants which are zoned 4, but have done well for me--Crested Gentian (very pretty blue flowers) and English Lavender "Munstead". The lavender looked a little dicey this spring, but it's coming along fine.I don't know where you are in Zone 3. I am in Northern Ontario and it can go to -40 in winter.

chickadee - Mulching over winter eventually compresses and it doesn't really affect the warming of spring soil. It feeds the soil once it gets thawed and planting right through it works well. It is said that Nature doesn't like bare soil and I've learned that lesson myself. This winter I had a three foot thick layer of leaves on the garden compress to around 6" by Spring. The soil underneath was nice and fluffy and didn't need turning. I did rake it back though to add to the summer compost when browns get rare. The winter compost pile went on to the garden to keep Ma Nature happy. Hope it warms up for you.