Dig In: Garden checklist for week of Oct. 1

Surprise! Fall is making a (little) splash with a drizzly weekend.

Sacramento’s last day of September will be unusually cool and possibly wet, says the National Weather Service. Along with a 40% chance of rain, afternoon temperatures will be decidedly cool; Saturday’s expected high is only 68 degrees – 20 degrees below average for this date.

“Scattered showers and isolated thunderstorms are expected to continue today through tomorrow, though the majority of rainfall will occur today,” the NWS Sacramento office tweeted Saturday morning. “Watch out for slick roadways and minor ponding while driving.”

Less than 0.15 inches are expected in downtown Sacramento; north of I-80 likely will get a little more. That’s probably not enough to prompt turning off the sprinklers. Check your soil to see which plants still need a drink.

September ends our “water year” and it’s usually a very dry month. If we do get one-tenth inch of rain, it would push our September rain total to above normal. Before Saturday, September had totaled 0.02; average for the month in Sacramento is 0.08.

Although it feels very fall-ish this weekend, our summer heat isn’t over. Following this cool spell, we’ll have a few days in the mid 80s. Then, the weather service expects Sacramento to return to 90 degrees by Thursday and stay hot through next weekend. That heat may coax a few more tomatoes to ripen and will keep soil warm.

So, make the most of this cooler weather. Get to work on your fall garden:

* October is the best month to plant trees, shrubs and perennials. Plants become established – sending down deep, strong roots – faster in warm soil.

* Divide and replant 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.

* 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.

* 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 pumpkins and winter squash.