Dig In: Garden checklist for week of Oct. 20

It’s not the heat, it’s the humidity. Besides summer temperatures, that old saying applies to fire weather, too.

Right now, that dry wind has sucked the last moisture out of remaining summer foliage; that makes grasses extra crispy and very susceptible to wildfire. Don’t mow dry grasses in this weather; hitting a rock can spark a blaze.

According to the National Weather Service, the Sacramento Valley and Sierra foothills will remain under a red-flag warning into Saturday evening, though the strongest winds had eased by noon. Winds of 10 to 15 mph with gusts of 20 to 30 mph were predicted in the Sacramento area. The Delta had a forecast for winds of 20 to 30 and gusts up to 45 mph. Watch out for falling branches as well as fire danger.

Meanwhile, daytime humidity is down to 10 to 20%, says the weather service. Expect trees to start rapidly shedding their fall foliage.

That low humidity can take a toll on new transplants and seedlings, too. Keep those plants irrigated and evenly moist as they get established.

With the winds dying down, temperatures should be pleasant with afternoon highs hovering around 80 degrees. That’s average for late October in Sacramento – and perfect for gardening.

* October is the best month to plant trees, shrubs and perennials. Add a little well-aged compost and bone meal to the planting hole, but hold off on other fertilizers until spring. Keep the transplants well-watered (but not wet) for the first month as they become settled.

* Dig up corms and tubers of gladioli, dahlias and tuberous begonias after the foliage dies. Clean and store in a cool, dry place.

* Treat azaleas, gardenias and camellias with chelated iron if leaves are yellowing between the veins.

* Clean up the summer vegetable garden and compost disease-free foliage.

* Harvest apples and pears. Pick up fallen fruit.

* Harvest pumpkins and winter squash.

* Now is the time to plant seeds for many flowers directly into the garden, including cornflower, nasturtium, nigella, poppy, portulaca, sweet pea and stock.

* Plant seeds for radishes, bok choy, mustard, spinach and peas.

* Plant garlic and onions.

* Set out cool-weather bedding plants, including calendula, pansy, snapdragon, primrose and viola.

* Reseed and feed the lawn. Work on bare spots.