Gardening in April

April is the best month of Spring! Days start to hint of warmth to come, and leaves and flowers are sprouting. Most days it’s not too hot yet to spend any portion of the day outside. It’s a busy time in the garden. We’ll get spells of heat that are tempting to think Summer is here but hold off until later in the month to plant warm season vegetables until nighttime temperatures are consistently above 50 degrees. It’s a perfect time to prepare soil when dry enough, sow seeds and set out some transplants.

You can still plant ‘season adjacent’ vegetables that mature quickly to harvest before the summer intense heat. Plant radishes, lettuce, spinach, mustard greens, as well as herbs like basil, cilantro, and dill.

Mid-month transplant or sow seed for cucumbers, squash, melons, carrots, celery, chard, herbs, parsley and potatoes and summer loving onion sets.

Early April plant squash, cover 'season adjacent' vegetables under row covers on hottest days.

To keep soil evenly moist during the ever-changing daily weather, use row covers on the hot days to protect young sprouting seedlings.  If we are fortunate to have rain this month, scatter seeds the day before to take advantage of nature’s help to sprout these easily.

In late April you can begin to sow or transplant vegetables that prefer very warm weather like peppers, tomatoes, eggplant and green beans. If it’s a cool month hold off until May to seed green beans – they like the soil to be warm and seedlings don’t transplant well. Be sure to plant edible flowers like nasturtium and pansies. And add flowers to attract pollinators like cosmos, alyssum, zinnias and sunflowers.

Companion plant tomatoes, peppers, onions and basils together. Be sure to set cages on your tomatoes when you plant before they get too big.

Your native plants will become even more alert this month. Early spring blooms and new growth will be visible.  This month be sure that all old woody growth is cut back before new growth starts, if you want to control the size and shape of your plants. You don’t need to start watering until lengthy warm spells – that is, if you want to keep your plants from going dormant. In that case, water when temperatures exceed 80 degrees about ½” every 1 or 2 weeks for new plants, and less frequently for established plants. Remember these are native plants, adapted to the hot and dry of SoCal. If you give some plants too much water, like Ceanothus and Black Sage, it will kill them from root rot.

Ceanothus 'Concha' is in gorgeous bloom in April.

April is the last month that I’d recommend planting any new native plants (May is OK too if the weather stays cool). Ideally these are planted in the cool months of winter that allow them to get established before the summer heat. But if you have a late addition, you’ll need to keep it more evenly watered through the summer. This can be a challenge if you’ve added plants to established beds that have less water requirements. So, plan to hand water your new plants a little extra during the hottest weeks until the roots are established. And, be sure to mulch well around the base of the plant to help with consistent moisture. Expect the plant to grow slow, as it’s struggling a little – as compared to natives planted in the winter that will grow quickly.

Monkeyflower 'Jelly Bean Lemon', enjoy these vibrant blooms before this native goes dormant during the summer.

While you are in your garden and yard, continue to spend time weeding. Your goal is to pull these before they go to seed, otherwise you are caught in a never-ending cycle. But you can diminish the regrowth if you pull them small and young, which is also easier to do after a spring rain.

You may need to run your sprinklers this month, I recommend setting aside time to do this while you can watch it run the first 5 minutes. It never fails the first time I run a zone since Fall something will require repair (usually because I stepped on a dripper breaking it while weeding and pruning).

Enjoy this month by getting out as much as you have time!