Seed Germination Overview
Seeds are living organisms, they remain in a suspended or dormant state until exposed to the optimal conditions to germinate. Germination is the growth of a plant contained within a seed; it results in the formation of the seedling. Each type of seed prefers a certain soil temperature, moisture content, and soil depth to begin its growing cycle. These external conditions are most likely to resemble the natural habitat of the plant.
Through the imbibition of water, the seed coat expands and then cracks allowing oxygen to access the seed embryo. Therefore, ending the seeds state of dormancy by changing the metabolic rate of the plant cells and jump starting its growth pattern.
When germinating vegetable and/or fruit seeds for your garden you may want to keep in mind your climate zone. This will help you decide what vegetable/fruit types and varieties you would like to grow for a successful season. Your climate zone will also determine the timing of your growing season, of what to grow and when to start it.
Understanding Your Seed Germination Climate
Typically, information of your climate zone will include a “last frost date”, which is when you should be able to move any seedlings grown indoors outside. However, every season is different, making the “last frost date” an estimated average. I have had more success with my growing season by observing my surroundings rather than following the rule of the “last frost date”.
You may get as technical as monitoring soil temperatures in your garden space, or, just watching certain perennial plants in your area as the season progresses. Observing lilacs or cherry trees works well. When the trees are in bud phase you can directly seed the cold hardy varieties that typically germinate in the 40*-50*F temperature ranges. There are a wide variety of cold hardy plants; kale, chard, spinach, all lettuce, onions, carrots, beets, radish, cilantro and most herbs.
When in the leaf phase, you would seed again, your cold hardy varieties (for a second, later harvest), as well as anything that germinates in the 60*-70*F temperature ranges. These include squash, cucumber, eggplant, beans, etc… Any of these can be started earlier if you create a micro-climate zone using a cold frame, particularly, a cold frame with an automatic vent, greenhouse, or cloche.
Once the lilac or cherry tree is beginning to bloom it is safe to move any seedlings that require warmer temperatures and a longer growing season out into the garden space as well as to germinate more seeds for the 70*-80*F temperatures. For an easy transition, you can place these plants in the cold frame to acclimate/harden off to the fluctuating temperatures.
Pollination vs. Non-Pollination
It is important to know and understand the difference between heirloom, open pollinating, non open pollinating and genetically engineered when choosing your seed varieties, types, and origins. All heirloom seeds are open pollinating, however, not all open pollinating seeds are heirloom. To be classified as an heirloom it takes three generations of harvesting seed without cross pollinating with similar varieties.
Open pollinating means that the seeds collected from those plants will produce seeds to gather and will then germinate to create another plant. There is a big difference between hybridizing and genetically engineering. Hybridization is accomplished with the cross-pollination of plant varieties with similar genetic material to be paired, either through human influence to achieve a desired trait, or, through natural selection.
Genetic Engineering and the Consequences
Genetic engineering is the process of splicing genetic material that would be incompatible in nature, leading to unpredictable side effects. Designed in a lab for industrialized agriculture, these monoculture fields have been proven to adversely effect the surrounding ecosystems. The controversy involving genetically engineered seeds is complex, many of the side effects are still unknown and will only be evident in the future.
It may take some extra research, but we do not recommend buying any seeds from companies that produce genetically engineered seeds.
Cold Weather Vegetable Gardening Best Practices
Tilth can be defined as the character of soil that has been cultivated and prepared for planting, the soils degree of readiness for garden use.
The long-term fertility and productivity of soil can be accomplished through sustainable agriculture; maintaining soil nutrients with amendments, irrigation, crop rotation, and companion planting.
The Key to Vegetable Gardening
It’s best to think of your soil as a living entity defined by its biodiversity which needs to eat, drink and breathe rather than an inert body. The benefit of organic matter and other amendments is to feed the wide range of soil organisms, fungal and bacterial. With out these organisms your plants struggle to process and absorb nutrients from the soil which then limits the yield and nutritional value of food grown in that soil.
There are three soil mediums; sand, clay, and rock. Depending on your existing soil type, promoting your soil organisms can be a long and slow process with several factors to be considered. Sandy soils are the first to warm in the sun and the first to drop in temperature as the sun sets. Microorganisms struggle to take hold due to the extreme temperature fluctuations and water flowing through with ease and washing away existing organic matter carrying the microorganisms with it. The compost mediums help sandy and rocky soils absorb and hold moisture which in turn aid and maintain an even temperature. Clayey soils benefit from these compost mediums because they help break up the dense and sometimes compact soil particles allowing water to drain while also helping organisms and root systems to breath.
By adding compost mediums, all three soil types get a boost of nutrient levels increasing your soils biodiversity and readiness to accept plants and/or seeds. Sandy, clayey and rocky soils all benefit from manures as well as woody/ leafy compost. Over time the soil will change and be less likely to revert to its original raw state.
The bacterial and fungal organisms thrive beneath the soils surface hence the benefit of tilling and mixing amendments into soil as opposed to setting on the surface.
Tilling Best Practices
Over-tilling can be an issue, such as tilling too frequently, or as I like to think of it, bruising the soil, which exposes your soils micro-organisms to too much UV light, killing many and damaging membranes of others.
Practicing good tillage:
Tilling and/or mixing amendments into soil anywhere from 4″-15″ deep is enough when preparing soil for annual plants as well as many perennial plants. When planting trees, same rule applies, the only difference is you till and mix the soil 10″-15″ beneath where the root systems of your tree will be resting.
Manipulation of soil once, maybe twice per year is plenty. Timing is important, tilling in the middle of the growing season causes more damage to the soils microorganisms and fungal membranes, again, bruising and damaging their growth pattern. Early and/or late tilling is permissible for the biota enter a stage of dormancy and can rebound from the damage of tilling since they have a longer period of undisturbed growth cycle. If you are tilling or feel it is necessary to till more than that because your soil becomes compacted and hinders plant growth, know that there are better solutions. For example; using mulch between rows (dry straw, leaves, etc.) helps reduce water evaporation, maintains soil temperatures, protects biota from UV light, helps reduce stagnant water from puddling, and also hinders weed growth reducing competition for nutrients. Further more, over tilling and damage of the soils biota causes soil to become compact due to the breaking of layers of membranes.
Using your plants to your advantage. Certain plants have stronger root growth than others and will push deeper into the soil, up to 8′ deep, essentially tilling and aerating the soil for you. Other plants have a shallow root system that spreads along the surface of the soil. Neither plants root systems of which are competing against each other for water or nutrients and sometimes benefiting each other by either attracting pollinators or deterring pests, A.K.A. companion planting.
In conclusion “variety is the spice of life”. Planting and maintaining many varieties of plants season after season will promote good tilth and save you from excessive labor.
Cold Weather Vegetable Gardening
Life in Sandpoint Idaho presents a range of seasonal challenges for a self sustaining lifestyle. From possible feet of snow, to unpredictable frosts, and the intense daytime sun and bitter cold nights all in the same day. Some plants that are perennials in most areas are annuals in ours. "The Artichoke Story" reflects one of our gardening victories.
Growing Vegetables and Herbs in a Cold Climate
For the first two years the rosemary, tarragon, and artichoke's we planted would die each winter barely even flowering in the previous summer. With their awe inspiring blooms, delicious heart of the thistle bud, and admirable dance with the bees, we were bound and determined to include artichokes into our space.
Elise had suggested to me that if we had a cold frame we may be able to winter over with more success these "perennials" that we had found to be so challenging. I bet you have guessed by now, she was right! For two years we refined our cold frame design to weather our climate in north Idaho with great success. During those years our artichokes survived the winters with weeks of negative temperatures to grow larger and produce bigger blooms. Each winter we noticed the soil around the outside of the cold frame would freeze at least a foot deep, inside the cold frame, however, the soil remained pliable, creating an optimal environment for the artichokes to winter. We have also had great success growing leafy greens and herbs like parsley and cilantro in the cold frames, harvesting through the months of October to nearly the end of February.
At the end of December and most of January the developed plants would slow their growth and harvesting without shocking the plants becomes tricky. By the middle of March we would need to start opening the cold frame on sunny days. Throughout April and May plants would experience more growth, enough to harvest more easily. Having leafy greens and herbs not grown in California at that time of year was liberating and exciting.
How Cold Frame Gardening Solved the Problem
The learning curve for cold frame gardening is figuring out when and how much to vent the lid to achieve the optimal temperature range. Additionally, the structure of the cold frame needed to be durable, efficient, and practical.
It has been three years since we started making our cold frames designed and used in our garden. The design has remained unchanged aside from adding the option of an automatic venting system, eliminating the need to manually vent.
It is great fun to feel so emboldened in our endevours to garden with so much success. Next, I want to attempt sweet potatoes and peanuts.