Dig In: Garden checklist for week of April 19

Don’t put away that umbrella! And hold off on transplanting those tomatoes and peppers one more week; another heavy storm is coming soon.

According to the National Weather Service, Sacramento can expect “definite rain showers and thunderstorms” on Tuesday, with a 45% chance that those showers will start sometime late Tuesday.

This will be another powerful and cold storm system, dropping more than 1 inch on Sacramento, predicts the weather service. Temperatures are expected to drop, too, with Tuesday’s forecast high only 62 degrees – almost 20 degrees colder than this weekend.

Overnight lows also are forecast to drop back into the 40s – more bad news for tomato transplants. They need nights to stay consistently above 50 degrees (and warm soil, too) to start growing.

Our April rain totals are already tracking above average. So far this month, Sacramento has received 1.38 inches of rain. The entire month of April averages 1.15 inches.

After the rain, our weather pattern is expected to settle down into something more predictable – and maybe approaching normal. Thursday’s and Friday’s forecast calls for afternoon highs in the low 70s and overnight low of 46 degrees. Average for mid-April in Sacramento: Highs of 71 and lows of 46.

After this midweek storm, start getting serious about spring gardening. Flowers are blooming about three weeks ahead of schedule. That includes weeds!

* Get ready to swing into action in the vegetable garden – if you haven’t already. As nights warm up over 50 degrees, set out tomato, pepper and eggplant transplants.

* From seed, plant beans, beets, cantaloupes, carrots, corn, cucumbers, melons,  radishes and squash; wait on pumpkins until May. Plant onion sets.

* In the flower garden, plant seeds for asters, cosmos, celosia, marigolds, salvia, sunflowers and zinnias. Transplant petunias, zinnias, geraniums and other summer bloomers.

* Plant perennials and dahlia tubers for summer bloom. Late April is about the last chance to plant summer bulbs, such as gladiolus and tuberous begonias.

* Transplant lettuce and cabbage seedlings.

* April is the last chance to plant citrus trees such as dwarf orange, lemon and kumquat. These trees also look good in landscaping and provide fresh fruit in winter.

* Smell orange blossoms? Give citrus trees a low dose of balanced fertilizer (such as 10-10-10) during bloom to help set fruit. Keep an eye out for ants. If leaves look yellow, your tree may need an iron boost -- apply some chelated iron fertilizer.

* Apply slow-release fertilizer to the lawn.

* Thoroughly clean debris from the bottom of outdoor ponds or fountains.

* Spring brings a flush of rapid growth, and that means your garden needs nutrition. Give shrubs and trees a slow-release fertilizer. Mulch with a 1-inch layer of compost, which helps the soil, but keep it a few inches away from trunks and stems.

* Azaleas and camellias looking a little yellow? If leaves are turning yellow between the veins, give them a boost with chelated iron.

* Trim dead flowers but not leaves from spring-flowering bulbs such as daffodils and tulips. Those leaves gather energy to create next year's flowers. Also, give the bulbs a fertilizer boost after bloom.

* Pinch chrysanthemums back to 12 inches for fall flowers. Cut old stems to the ground.

* Mulch around plants to conserve moisture and control weeds.