This has been an equally confusing and rewarding year so far for gardeners along the coast of Orange County.
January and February were warm and dry; a false spring. March and April were unusually cool and damp; the average daily temperatures were more than four degrees below normal! Surprisingly, March was the coldest month of the winter season, colder than December, January or February. March colder than January? Yes, and that’s an historical gardening event.
From the perspective of the plants in our gardens, these cool, damp spring days have created a colorful and long-lasting display of flowers, albeit slightly later than usual. Over the next few weeks we will continue to see our heaviest bloom of the year, especially from local favorites like geraniums, fuchsias, delphiniums, azaleas, clematis and sweet peas. Roses are especially magnificent this spring, holding the colors of their flowers and opening slowly in the cool weather.
May’s warmer soils and longer days make this one of the best times to add many plants to your garden, especially those from sub-tropical climates. Citrus, avocados and gardenias would have done poorly planted a couple of months ago, but will root quickly in May’s warmer soil.
Likewise, warm season flowers like Impatiens, begonias, zinnias, lobelia, verbena, ageratum, coleus and lisianthus would have been a risk just a month or two ago, but are a sure bet now.
As promised, garden success is also knowing what not to plant at various seasons. When shopping a garden center this month, don’t be tempted by cool-season specialties such as pansies, violas, primrose, cyclamen, Iceland poppies, stock or snapdragons. This is also a poor time to plant most of California’s native plant species. There’s a time for every plant and in California, natives are best added to our landscapes during October, November or December; not now.
In the edible garden it’s time to give up on any lingering cool-season delicacies. Vegetables like lettuce, broccoli, Brussels sprouts, cabbage, and peas should be cleared to make way for tomatoes, peppers, eggplants, melons, corn and maybe even pumpkins. In the herb garden be sure to set in plenty of warm-season growers like basil, tarragon and summer savory.
Speaking of basil, most of us know that the season for this popular herb ends about October. Try as we might, it’s just too cool for basil to survive through the cool winter months. But there is an exception. I am particularly excited about variety called Green Pepper Basil (Ocimum selloi). I originally obtained this rare basil from a friend and horticulture expert in Southern Oregon.
I’ve grown Green Pepper Basil for three years now and I cannot recommend it enough. It not only grows right through the winter with hardly a hiccup, but it is a stunningly beautiful plant as well; producing abundant of small lavender flowers through most of the year.
Like April, this is a month to feed the entire garden. Almost everything is growing and flowering. Tiny capillary roots are rapidly removing nutrients from the soil and bringing pulling them up the roots and through the stems to the green leaves. Once there, the most important single process anywhere on earth takes place – photosynthesis. These nutrients combine with carbon dioxide, water, and sunlight to produce energy for the plant and oxygen for the rest of us.
Use a high quality, well-balanced fertilizer. Just yesterday, I spread 25 pounds of mild organic fertilizer on my own garden. One more bag for the rest of the garden, a fresh top dressing of organic mulch on the soil surface and I’m set for at least the next couple of months.
Don’t fret too much about the aphids you’ll see. Just hose them off with a blast of water from the hose and move on. Snails and slugs however, will cause general havoc if not controlled. Hand picking works well but isn’t for everyone. If you need to bait, use a safe and environmentally friendly organic product. Avoid the popular baits that are especially toxic to children, animals and soil micro-organisms.
Roses are in bloom, lavender perfumes the air, hummingbirds sip the sweet nectar and warm sunshine nourishes it all. Spring is finally here.
Ron Vanderhoff is the Nursery Manager at Roger’s Gardens, Corona del Mar