I have enclosed a visual aid to help out with this question. I'm trying to...
I have enclosed a visual aid to help out with this question. I'm trying to build a seven story forest garden with a keyhole bed center. I have placed the dwarf apple trees in a shelter belt formation. Each apple tree is setup in separate apple tree guilds consisting of a dwarf apple tree center, surrounded by grass suppressing bulbs: daffodils, camas, garlic chives; insectary plants: dill, fennel, bee balm; nutrient accumulators: yarrow, chicory, plantain; and mulch plants: comfrey, artichoke. Now in the photo you will see three x's. My question is, what are the best canopy trees to put in the three x's? Remember, I'm trying to build a 7 story forest garden.
Massac County Illinois
This is somewhat difficult for me to answer, as I am not a landscape architect. I can provide a little bit of information, but I think you may want to run this by a certified and/or licensed landscape architect before you start digging.
First: the apple trees require full sunlight for at least 8 to 10 hours per day. If the X's are to the north of the trees, then we are in good shape, and can plant pretty much anything. However, if the canopy trees will shade your apples, you are going to have some serious problems with their survival, as well as that of the herbs, grasses, and other plants.
Here is a link to Purdue's publication on Landscape Plants for Areas With Full Sun: http://www.hort.purdue.edu/hort/ext/Pubs/HO/HO_223.pdf . The plants are broken down into groups by size: the big trees start on page 3.
Once you have a few trees that seem interesting, you can look up more information about them by going to the Missouri Botanical Garden PlantFinder website: http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/plant-finder.aspx . Just type the tree's name in the search bar, and you can look up information such as size, soil and moisture requirements, pest problems, etc. If there are any problems, such as invasive spreading or weak limbs, this site will let you know.
It appears from the picture that the crabapples are being grown in containers. If this is not correct, then please disregard the rest of this paragraph. If you are planting into containers or raised beds, be sure there is enough room for the tree. These publications may provide more information:
If you need more information, please email me directly at the address below.