Seed growth chart
It takes a lot of work to perfect the planting charts included here. To create these charts, we look at clusters of the most common average frost dates for a given area and estimate how many weeks make sense to plant seeds before or after the last frost. It’s a bit tricky, and it’s all about averages.
First frost: The first time frost occurs in the autumn in an average year.
Last frost: The last time frost occurs in winter or spring in an average year.
First and last frost dates are recorded by government-run weather stations all over North America, and the average is based on a fifty-year history for each region. These dates vary widely by region, which makes the regional charts helpful — we hope. They are intended to offer general guidance for garden planning, but they do not account for exceptional weather year over year. They also don’t account for our changing climate.
Hardiness zones also have to do with cold weather, but are quite a separate concept. Hardiness zones are established by measuring how cold and extreme the average winter gets in a given area, and whether specific perennial plants might survive over winter there. We might say that Echinacea is hardy to Zone 3, but that only reveals that Echinacea is likely to survive over winter in Zones 3 and up. Zone 2 is likely too cold for Echinacea to make it through the winter.
Knowing one’s hardiness zone is handy when selecting perennial plants for the garden, but it doesn’t reveal much more than that. We don’t provide hardiness numbers for annual plants, as they are not expected to survive winter in any climate.
Also download the West Coast Seeds Crop Planning Tool to plan spacing as well as timing.
It takes a lot of work to perfect the planting charts included here. To create these charts, we look at clusters of the most common average frost dates for a given area and estimate how many weeks make sense to plant seeds before or after the last frost. It’s a bit tricky, and it’s all about averages. First frost: The
Learn The Six Plant Growth Stages
Plants’ lives may be as short as a few weeks or months, but they go through distinct changes as they grow just as people do. For humans, the progression is infant, toddler, adolescent, young adult, middle aged adult, and senior citizen, while plants go from seed to sprout, then through vegetative, budding, flowering and ripening stages. Similarly, the nutritional needs of people and plants change as they grow. This graphic shows how a plant develops (in this case, a tomato) and highlights the changing nutrient needs for plants as they grow.
Each seed contains a small parcel of nutrients that is all they need to germinate and begin growing their first pair of leaves.
As plants’ roots develop and spread, a boost of quickly absorbed, well-balanced nutrients fuels the rapid growth from spindly seedling to healthy plant.
Nitrogen is a key component of chlorophyll, the green pigment in plants, so it’s the critical nutrient when their energy is focused on growing stalks and foliage.
Phosphorus is in extra high demand at the start of a plant’s’ reproductive cycle, the transition from growing leaves to forming buds.
Potassium plays a primary role in producing and transporting the sugars and starches plants use up as they develop healthy flowers and fruit.
When flowers and fruit are verging on full maturity, they need a week or two of just water without nutrients, a process known as “flushing,” so they can use up all of the nutrients they have already absorbed.
THE STATE OF YOUR PLANTS
What stage of growth is your favorite crop at right now? We’d love to see how your plants are doing, so send us a picture at the Safer® Brand Facebook page, where you can interact with the organic growth community. Also, be sure to subscribe to the Safer® Brand E-Newsletter for ideas on using your favorite OMRI Listed® products and other helpful garden articles about gardening and lawn care.