Do larger vegetable seeds result in higher yield or bigger fruit?

Answer: The answer to this question depends on whether you are asking about seeds in general or about different seed varieties of the same fruit.Regarding seeds in general, there is much literature about the fact that plants with larger seeds emerge faster than plants with smaller seeds and therefore have an evolutionary advantage. Early emergence gives plants speedier access to localized nutrient sources and will give them advantage over plants that germinate later in the same spot.Regarding different seed varieties of the same fruit, ATTRA is unaware of any research that shows a correlation of bigger seed size to bigger average fruit size. Take tomatoes, for example. There are many varieties?some produce small, cherry-type fruit and some can produce huge, two-pound fruit. But the seed size for each is the same. For any given seed variety, the catalogue or supplier from which it is purchased should state the average fruit size at harvest. For some vegetable categories, you could make the case that there is a difference in seed size and fruit size in related fruit products, say yellow squash and zucchini squash. The zucchini squash has the bigger seed and one can let an individual zucchini squash get really big, say two feet long and weighing four to five pounds. Yellow squash will not get that big. But one must question the reason to let an individual zucchini fruit get that big. In the commercial trade, the highest monetary returns go to zucchini squash that is six to eight inches long. Fruit that is larger than 18 inches really has no commercial value. The same can be said of yellow squash. There is a size limit to what is called #1 fruit and fruit larger than that limit gets less valuable as it gets bigger.The only vegetables that are almost always rewarded for ever-increasing size are tomatoes and bell peppers, and even then, there is an upper limit on size. Tomatoes are classified as extra large when they get to a diameter of about three inches. Fruit larger than that is sold, but anything over about four inches starts getting viewed negatively by the trade because really big fruit tends to go bad much quicker than smaller fruit. And besides, what customer wants to pay $5 for one tomato? Of course, there is one exception where bigger fruit is better: growing the “biggest” something for some kind of contest or county fair prize. There are still some pumpkin-growing contests around in the Northeast and even some “biggest watermelon in the county” contests around in Texas and other southern states. But these outrageously large fruits are the result of production process, not seed size.