Leave the leaves
Happy fall – or is it? What fun last week’s weather brought! A little rain, thunder, rainbows and wonderful sunsets. My mood was totally refreshed with the rain and the fields around here have a welcome haze of green.
But now with highs in the 90s for several days, real fall is still a ways off. I will be back to watering, with special care for the young transplants of cool season crops in my garden. They will appreciate a cooling afternoon drink after a hot mid-day. But since the days are so much shorter, run times of most irrigation systems can be decreased now. Tomato plants ripening their last fruit may not need any more water at this point, as the fruit will pull moisture from the plants.
I’ll also be looking closely at the young brassica plants – broccoli, cabbage, kale and kohlrabi – for tiny cabbage worms. I want to pick them off before they start munching leaves and set back these plants. These are critical days for the fall crops to put on size before days get even shorter.
“Fall” is what leaves do this time of year, and I’m always saddened to see this wonderful resource treated as waste to dispose of. Around the neighborhoods, leaves are being blown and raked into bags or yard waste containers. Soil is left bare and naked, with a hard surface that will be beaten harder by rain. Such soils are starved of the organic material that could feed the soil organisms during the damp season along with providing cushioning and pore space. An organic mulch – like leaves – will protect soil from erosion and compaction while allowing it to absorb rain. While politicians talk about increasing water storage, we can make a dramatic difference this fall and winter by capturing rain instead of sending it down storm drains. Leaving leaves, amongst other techniques, will make the ground around us much more absorbent.
What about big leaves that blow around, or mat up, or leaves that could harbor and pass along diseases? You can easily turn a big pile of large leaves into a much smaller amount of nice, uniform mulch by raking dry leaves into windrows and running a lawn mower over them. You can add leaves from driveways and patios to the windrows, or just spread them around trees or open spaces. A thick mulch put down now will prevent many weeds from growing too. If diseases on the leaves of fruit trees, berries or roses are a concern, wait until all leaves have fallen, then cover with a layer of rough compost, or tree trimming chips (aka arbor mulch), or leaves from another type of tree. Avoid using leaves from walnuts, eucalyptus or live oaks for this purpose. These leaves are best left under their trees. Always remember to pull back mulches from the base of fruit trees so there is a narrow ring of bare soil right around the trunk. This will help prevent borers, rodent problems, and bark rotting.
As summer crops fade, it is important to pull or cut them out and compost the remains, or to turn them into the soil. If you’ve always thought about making your own compost, fall is a great time to start. You should have plenty of material and a bit more time than the mad rush of spring. Compost started now should be ready to use next spring. In addition to the great guide I mentioned last year and listed below, there is a very good short video of making compost done by local Sonoma County gardeners and made by our friend Terry Allen, with Seeds of Change. See:
Watch the video: https://www.youtube.com/watch?v=Pne1fNsq6Uc.
And/or download the Master Gardener composting guide.
Have some space and want to take advantage of the warmth? You could still plant directly from seed: bok choys, mizuna, mustard greens, and other fast growing Asian greens. Arugula, radishes, spinach, and mache (corn salad) can go in now too. I sowed my beloved escarole and other winter chickories just after the new moon a few days ago.
Enjoy the warmth, with prayers for real rain soon.