Fall Planting
By Andrea Peck
I've heard that fall is the time for planting ornamentals, but I must confess I have always wondered why. Logically, I'd assumed that the reason fall planting is best is to gain the benefit of rain. But, California, as a rule, does not weep measurable precipitation during those three grand months. Contrarily, the fall months are often some of our warmest and driest, particularly along the coast.
So what gives?
I decided to dig a bit deeper and I discovered that much of the interwebs is composed of forums that discuss the merits of vegetable planting during the fall. Brussels sprout and broccoli fans are consistently represented and there is a bit of showing off with the mention of exotica, such as watermelon radish and red perilla. There are fancy photos and book loads of recipes involving kohlrabi and spinach. Finally, I unearthed it: the reason we plant in fall.
And confound it; no matter the angle that I view gardening, it appears that the future-think approach is the one with the most rewards. If you dial back to spring, you will see what I mean. Planting in spring is notoriously popular – you can visualize the frenzy, as ladies and gentlemen fling themselves amongst the colorful spring flowers and vegetable starts.
Such a relief from the doldrums of winter!
But, tumble into this marketing ploy and you will come to learn that planting in spring lends little support for the average new ornamental. Think of summer - it's not hard with that dry desperate heat still smoldering around us. Now think of that poor plant that you stuck in the earth during the spring. You watered it for a bit, assuming it would soon root in and stand on its own. Then summer waltzes in with its water restrictions and phenomenal temperatures. If you are like me you see a number of dead “new” plants creating texture and sculptural interest in your landscape. Mine were even drought tolerant.
Planting during the fall is the opposite. Just as you are finished nurturing your little plant infant, the winter steps in to take over with the real irrigation manna.
But, hold fast! There are other reasons that make fall planting ideal. Apparently plant shoots require fewer nutrients as winter dormancy approaches. Also during the fall, carbohydrate “food” that is produced in the leaves is moved to the roots – this promotes growth and survival.
Autumn generally shows a temperature shift, as well. The temperature may continue to feel overwhelming, but the days are quickly becoming shorter and the nights cooler – a perfect combination for plant growth. Warm days keep soil temperatures elevated which encourages root growth, while the overall cooler temperatures lessen moisture loss through the leaves.
Winter brings changes which promote a hardy plant over time. Rain provides clean moisture and nitrogen. Colder temperatures slow top growth which allows rain and cool soil to focus on root growth. Warmer air temperatures arrive with spring. The fall plant, allowed the extra resources of initial warmer soils, cooler air and the subsequent winter rains and cool temperatures, is primed to support top growth. Root growth continues during the spring which allows the plant a better chance towards survival during the increased dryness and heat of summer.
Now, with all that nourishing and care – and planning - your little one is ready to show off a full flush of foliage.