One of the things I love about gardening is the experimental nature of it. It is a great venue for applying experimental methods to the world. Every time you plant a seed you have the opportunity to plant a similar seed under a different condition and see if that matters. For example, I just finished planting some tomato and pepper seeds that I will start under some grow lights. I have some left over seeds from the packets that I can also plant outside in my backyard greenhouse. I can then observe what benefit there is to starting seeds under grow lights versus direct seeding into greenhouse soil. I can potentially observe germination rates, the relative mortality of germinated plants, the effects of hardening off/transplanting for seedlings started under grow lights, days to harvest for the differently grown plants, etc...

Experimentation also means trying something out that may be kind of bizaare to see if it works or not. In this regards, I built a cold frame this year and started different varies of lettuce, carrots, kale, sweet basil and chives in it this spring. I also planted something else. In the late fall of last year I processed some plums into plum wine. I dumped the extracted plum seeds into the soil where I built my new cold frame. Instead of removing the plum seeds before I planted, I decided to spread them around and covered them with 3 to 4 inches of new soil. I planted my veggies into the top layers of this soil in the early spring. Yesterday I observed what I believe is the first plum seedling sprouting up amidst the lettuce.

This can perhaps be viewed as an example of vertical stacking; but instead of stacking one row of veggies above another row of veggies to maximize growing space; I am stacking seeds in the soil at different layers to grow quite different types of plants in the same growing area - veggies and plum trees.

Bill Mollison, the father of Permaculture, famously said:

The yield of a system is theoretically unlimited, or, limited only by the information and imagination of the designer.

He often enjoyed showing how you could keep stacking functions within the same limited area to get more and more yield out of that area. An important goal for alot of (sub)urban gardeners is arguably to maximize the yield of their growing area. It requires experimentation in both the methodical and crazy senses to find new methods to reliably increase yield.

Last night, I started watching Elon Musk's recent Ted Talk where he talks about ways to increase mining, traffic and energy yield (among other topics). Perhaps one of the secrets to Elon's thinking is his ability to see how yield can be increased beyond what others can imagine.