That's the thing about gardening...local conditions are very often determinative of success/failure. Learning what works and does not work in your local conditions is so important. However, I've found that often one can "push the envelope" on local conditions with certain practices. It's those practices that really distinguish some gardeners.
Metrics based on your local conditions are a key management tool for gardeners who wish to raise a large part of their annual food supply.
For example, by using a metric of the ratio of new potatoes to seed potatoes, I have an accurate way to produce the amount of new potatoes needed each year. I like to target a production amount of 200 pounds of new potatoes and I know for certain, as certain as anything in gardening gets, that 20 pounds of seed potatoes, regardless of number of eyes will yield over 200 pounds of new potatoes in my local environment.
Similarly on onions, I use a metric which is determinative of amount of onions desired. For that, I know it takes on average one onion set per pound of bulbs produced. Like potatoes, I target over 200 pounds of onions each year and know again for almost certainty that 200 sets will yield at least 200 pounds of useable onions while providing ample green onions during the growing season while I await the big bulbs.
For corn it gets a little more complex. I use number of seeds as the key metric to determine plantings and use production amount needed to determine the number of plantings. For example, I know from experience that about 300 ears of corn (some eaten fresh, some given away, and some frozen) is my annual target production amount. I can reasonably expect to be able to process about 100 ears of corn maturing at the same time...more than that and much is wasted.
Hence, three plantings are required to achieve the production target of 300 ears. I know that I get about one ear of usable corn for every two seeds planted in my local environment....recognizing that plants must be thinned and some losses will always happen along the way. Hence to get my annual target of 300 ears of corn, I need three plantings spaced a couple of weeks apart, each of 200 seeds. That will generally yield 100 ears of usable corn per each planting. Yes, I actually divide my corn seed out into three 200 seed plantings counting them out .
Similarly for beans, tomatoes, and other veggies we grow. Metrics tailored to local conditions are integral part of it.
I do the same thing. I have learned super sweet corn has a very poor germination rate 50% to 60% and super sweet is a 72 day crop, plants are small, ears are small, kernels are small. If I plant 500 seeds and 250 germinates small ears are equal to 125 ears of a large 92 day corn. NOW I grow G90 bicolor 92 day corn I am getting 98% germination rate, I only need to plant 250 seeds but I plant 300 just incase its a bad year. This year was a bad flash flood rain over & over 50°F cold mud, corn seeds don't like cold mud. Finally rain stopped garden was dry as desert no rain for 3 weeks. I planted seeds and watered seeds every day very slowly 270 seeds finally germinated over a period of 1 week. G90 is better than Peaches & Cream or any other bicolor corn plants are 8 ft tall, wife puts about 50 pints in freezer bags every summer.