Question
Hi,
  First, thanks very much for taking the time to consider my question.  Your advice is very much appreciated.  
  A friend has asked for help with a long bed that is on the border of what will soon be a rental property in rural Connecticut.  Currently, the bed is overgrown with weeds.  There are some phlox and hydrangea scattered about.  We will remove the current growth and start from scratch. The work will be done in September.  I have the ability to do the actual planting, but it is the design and overall concept that I need help with.  This bed is about 75?long and 6-7?deep.  It receives morning sun and filtered shade after that.  My friend wants a low maintenance informal perennial border, which will make the site attractive without much care once established.
  My first question has to do with landscape fabric.  Is this an essential to such a bed?  With such a big area, will the fabric actually keep the planting from ever filling in?  If I use the fabric, do I need to cut a large planting hole so the plants have room to expand?  Do I need to add new topsoil to the entire area?  The soil looks to be reasonably well drained and I will fertilize before planting?
  Secondly, I am looking for suggestions for perennials for this situation.  The colors are not particularly important to my friend who basically wants an attractive border for this old farmhouse.  I would like to provide something that will provide an interesting view throughout the season厀ithout much maintenance.   Can you suggest some reliable varieties of plants that I could plan around for this site with morning sun?  I think I will be able to compose an informal design, taking into account height, color and season of bloom if I have the varieties to work with?
  Would it be okay to place some interestingly shaped rocks from the property within the border to break up the view and take up some space in this large boarder?  Are plants not noted for their blooms, like tall grasses, worthy of inclusion?  And lastly, I promise, can you estimate how much mulch I would need to order for a bed this size (approximately 75抶6??
  Thanks so much for any advice you can give.  I really do appreciate your expertise.                        
                    Sincerely, John Vozab  

Answer
Hot dog!  A record 9 questions in one e-mail...  

Happy to help out:

For low maintenance, the weed barrier/landscape fabric just aids in making the weeds easier to pull up (and, you will get weeds!).  Is it essential?  No.  The hole only has to be as big as the planting hole, and I just slash one with an "X", and then peel it back like a banana skin, exposing the soil underneath.  Will it slow a plant from filing in?  Depends on the plant.  It needs to send out "rhizomes" (like bamboo) to fill out the space, then yep - probably not a good idea.   If they are spread with "runners" like Virginia creeper or strawberries, then the fabric probably won't slow it down.

Lets see - new topsoil?  Looks can be deceiving.  Maybe worth the $30 to have it tested for fertility.  I don't know for sure, but I would at a minimum I'd at least some fertilizer - and this can be added either before OR after planting, except for trees; they usually like tablets in the planting holes.

Here is a Connecticut website on planter bed preparation:
http://www.canr.uconn.edu/ces/garden/NewGardenBeds.htm

Suggested shade plants - too many to list, but the "big" ones I'd recommend are Dogwood, Alpine Current, Rhododendrons, Coral Berry, and Yew - all shade tol.

Here are a few websites with photos of shade-tol. Plants that grow in your area:

Shade Tolerant (they're in Litchfield, Conn.):
http://www.whiteflowerfarm.com/perennials-for-shade.html

(And another one in Wallingford, Conn.):
http://www.pallensmith.com/newsletter/2003/news_052303a.htm

Another site (in Minnesota):
http://www.ricecreekgardens.com/shade_plants/index2.html

Plus, if you are REALLY rural, you might consider avoiding "deer food" plants...your local Ag Extension have great suggestions for avoiding them, or scattering the deer from your plant bed.

O.k. to place rocks?  Heck yeah.  As you mentioned, it's a good way to break up a flat, 75-foot long planter bed.  Plus, they use a lot less water.

Tall grasses?  They can be a bit of a maintenance issue, because to keep them looking good, you usually have to cut them back once a year (in the Spring).

And, finally, the math:  In our area, we use 4-inches of mulch (1/3rd of a foot, or 0.33'), so;

75'long x 6'wide x 0.33 deep = 148.5 cubic feet, divide by 27 to get cubic yards, or 5.5 c.y.  I round up for "settlement" and loss due to other reasons, so 6 c.y.

For every inch you raise or lower this mulch depth, add/subtract 38 cubic feet (about 1.4 c.y.).

Think I got 'em all. If I missed any, just post a follow-up question. Enjoy your project!  -Marc