Which preposition to use with buckwheat

in Occurrences 2%

The young lady, in a checked apron and mob-cap, greeted her friends with a dish of buckwheats in one hand, and a pair of cheeks that proved she had been learning to fry these delectable cakes.

of Occurrences 1%

Wild buckwheat of many species is developed in abundance over the dry, sandy valleys and lower slopes of the mountains, toward the end of summer, and is, at this time, the main dependence of the bees, reinforced here and there by orange groves, alfalfa fields, and small home gardens.

on Occurrences 1%

To be sure, we grew some sod-corn, and some sod-potatoes, and sowed some turnips and buckwheat on the new breaking; but after my hair was gray, I found out, for the first time as we all did, that a fine crop of flax might have been grown that first year.

Which preposition to use with  buckwheat