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For very brief information, see attached scan from American Home Landscapes: a Design Guide to Creating Period Garden Styles. This book is available in our library.. 

The most detailed description I could find was in this article describing New York row houses (plantings would be very similar to Philadelphia and other East Coast row houses):

American Gardening, 1893 "City Gardens, A Contrast - Back Yards in New York and Florence" vol. 8(2)pp. 100-101

See also:

Gardeners' Monthly and Horticulturist, "A Small Yard". Thomas Meehan, ed. Vol. 29, 1887 pp. 102-103

Row House gardens are briefly mentioned on this website:

8 Garden Designs for Old Houses

And for background information on Philadelphia row houses see:

Row Houses article in Encyclopedia of Philadelphia