1
general::
Also, hard row to hoe. A difficult course, hard work to accomplish, as in He knew he'd have a tough row to hoe by running against this popular incumbent. [First half of 1800s]
American Heritage Idioms
2
general::
Phrase(s): a tough row to hoe [and] a hard row to hoe
Fig. a difficult task to carry out; a heavy set of burdens. • It’s a tough row to hoe, but hoe it you will. • This is not an easy task. This is a hard row to hoe.
McGrawhill's American Idioms And Phrasal Verbs