Question
What type of soil do japanese maples prefer.  What kind of fertilizer, etc would you reccommend to bring out vibrant colors and enhance growth.  any other advice you could provide me would be appreciated.  I live in central Iowa and wintering is of great interest to me.

Answer
In general, Japanese Maples are very cold hardy.  They do like organicly rich soil, however, so a yearly application of compost or composted manure (2" layer) is the best thing you can do for them.  Put two inches of this down around under the dripline every fall, and then an inch of bark mulch in the spring is ideal.  Water deeply once a week in periods of drought.  If you have good soil (loam or clay) and are putting this organic matter down you don't really have to fertilize unless the tree does not seem to be doing well.  I am partial to organic fertilizers myself because they are slow release, so if you do fertilize do so in the spring and apply sparingly.  The organics - compost or manure - are key.  These maples will grow in part shade or full sun.

I hope this helps!
C.L. Fornari