Seeds are amazingly packaged little powerhouses of genetic potential. The whole gene-chromosome complex, commonly referred to as Mendelian Genetics, is just part of the story. How they store enough energy to get their roots and shoots started, how they protect all this in their unique form of biological amber, is quite remarkable in its own right.
No matter what path a seed takes to get swaddled up and sent off into the world to procreate its species, there are some basic characteristics that are ubiquitous. The first thing parents do is protect their children—it’s the same with seeds. Seed coats must protect the physical biomass of the protein and starchy structures within. These coatings also have some genetically programmed mechanism that informs the inner sanctum that all is well, or not. Be it temperature, moisture, oxygen levels or a host of other factors, each and every species has a mechanism in its seed to wake up Junior and expose her to the new world. We see this with the progression of germinating weed species in the field throughout the season. Seemingly overnight, a flush of weed seedlings will appear like a carpet, all the exact same shape, size and color. We know who they are; we saw their parents. We were expecting them; they come every year to Elmwood Stock Farm, their arrival helping to inform our estimate of the arrival of spring. We have the tools to unearth, bury or decapitate them, but their siblings and offspring of many generations lay in wait for the next opportunity to come to life.
The presence of weeds is a window into what’s going on in the soil. Why are those weeds in that place? If the ground becomes compacted and the air chambers within it minimized, weeds will emerge that had never been seen in that place. Interestingly, albeit counterintuitive, weed species whose composition is high in a particular mineral, say zinc, will flourish in a soil low in zinc. These plant roots will scour throughout the soil, desperate to find zinc and deliver it to the leaves and fruit. In the infinite wisdom of Mother Nature, when we cultivate these plants back into the soil or they seasonally die back, the zinc will be released into the rhizosphere, thus ameliorating the zinc deficiency of that soil.
Selection and Saving
Having the right little bundle of joy is not easy to come by. We rely on organic seed farmers to nurture the parent stock and harvest the seed with optimum care. In organic farming systems, the parent stock has been carefully cultured for generations to not only yield the best-tasting products, but to be hearty and productive. Seed farmers watch the fruits ripen, often letting them mature well past the time to eat them, allowing the seeds within to complete the work of zipping up their genes and securing them for later in life. Great care must be taken to clean, dry and sort only the best of the best to ensure a strong, viable crop will ensue. Having been raised in an organic system, attributes like disease resistance can be evaluated and passed on to the next generation.
We save seed for some crops we grow, but being the viable little organisms they are, there are countless opportunities to cause harm to the zygote within. Harvesting, cleaning, sorting and packaging must be done with care and diligence. Each crop has quirks in how this process needs to work. Consistent temperature and moisture is key. Knowing when they are dry enough is tricky, and air-dried may not be good enough. Daily temperate and humidity swings, along with rainy spells, may cause slight shrinking and swelling of the seed coat, using up some energy it will need later to give the little sprouts the boost they need. To call a farmer a good “seedsman” is a badge of honor. We have some corn, bean and tomato varieties that go back decades that we nervously tend to each fall like first-time parents. The availability of high-quality organic seeds has greatly improved, thanks to the pull of your support of local, organic foods.
As agriculturalists, our work is to manage environments in a controlled manner to make food for people. So with the 250-plus vegetable varieties we grow for you, each one has its own unique properties to be considered. We handle them in batches of like kinds and germination requirements based on their characteristics. The members of the brassica family (broccoli, kale, cabbage, collard, etc.) have similar germination requirements, although they mature very differently. These small, perfectly round seeds can easily be distributed into the cells of a seeding tray with simple vacuum technology. Some seeds that are not perfectly round can be made round with a clay coating to facilitate the use of this technology. (The photo to the right is “pelleted” lettuce seed on the vacuum seeder.) Not all species—or not each specific variety of a species we like—are available in pelleted form, so we must flick, scrape, tap or otherwise distribute them into the seeding-tray cells, one by one. The trays are then moistened and stacked in a homemade germination chamber, which is a warm, moist room where the seed coats swell and crack, usually in a few days, signaling the time for the roots and shoots to emerge.
The formation of a plant’s vascular system requires a great deal of energy, which is supplied by the starches that are stored in the seeds. The radicle, or first root, emerges from the seed and naturally turns downward, in search of nutrients and the medium to anchor itself. The combination of peat, perlite and compost that we use in our seeding mix is loose enough to allow easy penetration of the radicle and allows air into the root zone to minimize the energy required for establishment. Soon, the first leaves will emerge from the surface to begin photosynthesis, to transfer the nutritional requirements to the new plant—no longer the seed—to complete this miraculous transformation to the next generation.
There are two basic types of seeds: monocots and dicots. Monocots are the spiky emergers, like corn, onions and grasses. As soon as the new root signals back to the seed that all is well in the ground, the shoot spears its way to the surface in search of sun. If the conditions are not just right, this journey is made difficult, and more stored energy from the seed will be required. Planting in soil that is colder than optimum can be one of these factors, so we often must grit our teeth and hold off on planting a crop, even when it seems like time to go. Monocots have it easy compared to dicots. Dicots keep their head down, and their bent and crooked neck burrows up to break into the new world. This tender, little shoot then pulls with it two cotyledons (hence dicots), which are leaflike structures that have much the same benefits as colostrum in mammals. They are specialized to develop the hormone and vascular structures the plant will need for survival. Once the photosynthetic energy kicks in, the seed is spent.
The soil is said to house a seed bank—an immeasurable volume of weed seeds, awaiting the right conditions to germinate and grow. We will use all the tools in our organic-farming tool box to minimize their proliferation while nurturing the little seeds of the plants that sustain us—and you. The early greening of pastures and early germination of weeds we are seeing this year indicates an early spring is upon us. The dramatic deep freeze this week will not make the baby beet roots and pea shoots we have out there for you very happy. The arms race of controlling the wild seeds, while culturing the desirable ones, is well under way on Elmwood Stock Farm. The dance with Mother Nature has begun. Wish us luck. —Mac Stone