Vesta is a farmer who sells seeds. You can buy her seeds here. You just need to tell her, she is always behind the desk.
Here is the seed list:
Spring
Turnip - 120 G. Harvest in 5 days.
Potato - 150 G. Harvest in 8 days.
Cucumber - 200 G. Harvest in 10 days, regrows in 5 days.
Strawberry - 150 G. Harvest in 9 days, regrows in 2 days

Summer
Tomato - 200 G. Harvest in 10 days, regrows in 3 days.
Corn - 300 G. Harvest in 15 days, regrows in 3 days.
Onion - 150 G. Harvest in 8 days.
Pumpkin - 500 G. Harvest in 15 days.

Fall
Eggplant - 120 G. Harvest in 10 days, regrows in 3 days.
Carrot - 300 G. Harvest in 8 days.
Sweet Potato - 300 G. Harvest in 6 days, regrows in 2 days.
Spinach - 200 G. Harvest in 6 days.

All Time
Rice - 600 G. Grows in 60 days. It produces 100
Wheat - 600 G. Grows in 60 days.