Dig In: Garden checklist for week of June 14

Some like it hot? We’ll soon find out as triple-digit temperatures scorch the upper Sacramento Valley.

According to the National Weather Service, “dangerous heat” is forecast Sunday through Tuesday with afternoon highs possibly reaching 105 to 110 degrees from north of Yuba City up to the Redding area. 

Sacramento itself is expected to see highs in the upper 90s through Tuesday, then some cooling into the upper 80s. The normal high for this week is 86 degrees.

On any day with an extreme forecast, concentrate on getting out early and keeping your garden (and yourself) comfortable. Plan on irrigating your garden first thing – before the heat arrives.

A “dangerous heat advisory” means high risk of heat stress or illness for “entire population,” says the weather service. Animals need protection, too; give them shade and water.

The weather service also offers this advice for high heat:

* Stay hydrated.

* Avoid being outdoors in the sun between 10 a.m. and 6 p.m.

* If you have access to air conditioning, use it.

* Stay in a cool place, especially during the heat of the day.

Fortunately,  Sacramento will be back to the low to mid 80s by Thursday. Friday’s forecast high is “only” 82 degrees – great gardening weather. Any tasks that can wait, put off until then.

* Let the grass grow longer. Set the mower blades high to reduce stress on your lawn during summer heat. To cut down on evaporation, water your lawn deeply during the early hours of the morning, between 2 and 8 a.m.

* Tie up vines and stake tall plants such as gladiolus and lilies. That gives their heavy flowers some support.

* Dig and divide crowded bulbs after the tops have died down.

* Feed summer flowers with a slow-release fertilizer.

* Mulch, mulch, mulch! This “blanket” keeps moisture in the soil longer and helps your plants cope during hot weather.

* Avoid pot “hot feet.” Place a 1-inch-thick board under container plants sitting on pavement. This little cushion helps insulate them from radiated heat.

* Thin grapes on the vine for bigger, better clusters later this summer.

* Cut back fruit-bearing canes on berries.

* Warm weather brings rapid growth in the vegetable garden, with tomatoes and squash enjoying the heat. Deep-water, then feed with a balanced fertilizer. Bone meal can spur the bloom cycle and help set fruit.

* Generally, tomatoes need deep watering two to three times a week, but don't let them dry out completely. That can encourage blossom-end rot.

* Feed camellias, azaleas and other acid-loving plants. Mulch to conserve moisture and reduce heat stress.

* Cut back Shasta daisies after flowering to encourage a second bloom in the fall.

* Trim off dead flowers from rose bushes to keep them blooming through the summer. Roses also benefit from deep watering and feeding now. A top dressing of aged compost will keep them happy. It feeds as well as keeps roots moist.

* Pinch back chrysanthemums for bushier plants with many more flowers in September.

* From seed, plant corn, pumpkins, radishes, squash and sunflowers.

* Plant basil to go with your tomatoes. There’s still time to plant melons, pumpkins and squash from seed.

* Transplant summer annuals such as petunias, marigolds and zinnias. It’s also a good time to transplant perennial flowers including astilbe, bidens, columbine, coneflowers, coreopsis, dahlias, rudbeckia, salvia and verbena.