The SECRET to propagating roses is said to be the "potato"! TIP: Before planting rose cuttings, push the bottom end into a small potato, which keeps the cuttings moist as they develop roots. It sounds crazy, but apparently it works really well.
Tomatoes and potatoes can be grafted together because they are members of the same plant family. Called the TomTato, each plant can yield more than 500 sweet cherry tomatoes as well as a decent crop of white potatoes.