For years, the notion that we should begin planting in October and wrap up by March puzzled me. With the allure of "Spring Planting!" campaigns saturating the media and stores, and the beautiful weather outside, why the advice against planting? Let's delve into the rationale behind our designated planting season.
Whether we're discussing vegetable gardening, desert-adapted landscapes, or native plants, our planting season begins in October and extends through March. Beginning in fall allows our plants a solid 9-month window to establish themselves before the scorching summer temperatures arrive. As we've discussed in previous newsletters, the initial year is pivotal for a plant's establishment, laying the groundwork for its future growth. Fall temperatures offer an ideal climate: warm days, which may still peak at 100 degrees, coupled with cool nights. With the shifting sun angle and shorter days, even on exceptionally hot days, the heat doesn't stay around as long. This creates optimal conditions for seed germination in warm soil and prevents seedlings from being battered by strong winds. Moreover, plants purchased from stores benefit from warm soil for root growth and a temperate transition into their new home. Remarkably, up to 80% of yearly root growth occurs in the fall, when days are shorter and temperatures milder.
The later we plant in the year, the more water and care are required to ensure survival through the summer. Research indicates we need at least 6-8 weeks before consistently facing 100-degree temperatures. Beyond this threshold, a plant's ability to endure the summer diminishes significantly.
Now, circling back to this year, we had some seriously chilly days stretching into March and April. So, why can't we still plant when the weather seems pleasant? The answer lies in recognizing that a cool spring doesn't guarantee a cooler summer or delayed extreme temperatures. We rely on historical data, not some magical crystal ball to tell us when the heat's coming. Considering that plants require a minimum of 6-8 weeks to establish, it makes sense to halt planting around the end of March. This doesn't imply our gardens won't thrive - in fact, mine looks its best at this time of year. It just means we should hold off on planting, or if we must plant, be diligent in our irrigation practices.