Dig In: Garden checklist for week of April 18

That little tomato seedling will get a good boost from the warm weather the next few days. But if your plants aren't in the ground yet, hold off until the temps drop back down -- the seedlings will be less stressed when they do go in. (Photo: Kathy Morrison)

Our spring weather will quickly feel like summer this weekend as a mild heat wave spikes temperatures.

According to the National Weather Service, several Central Valley locations will see their first 90-degree days of 2021 on Sunday and Monday. Fortunately, afternoon highs will cool down just as quickly. We’ll be comfortably back in the low 80s by Tuesday.

This warmth will stick around after dark, with overnight lows staying above 50. That’s warming the soil, too; good news for tomato gardeners!

Newly transplanted seedlings will be comfortable enough to get off to a good start. But wait until after Monday to put new plants in the ground. They’ll have less stress if they don’t have to endure 90-degree temperatures their first days in their new homes.

Remember to keep transplants and newly planted seeds watered. There’s still no rain in sight.

Also on this week’s to-do list:

* Feed shrubs and trees with a slow-release fertilizer. Or mulch with a 1-inch layer of compost.

* 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.

* Set out tomato, pepper and eggplant transplants.

* From seed, plant beans, beets, carrots, corn, cucumbers, all melons, radishes and squash.

* 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.