Gardeners in Orange County were reacquainted with “May Gray” last month.  Now, we’re in the more familiar territory of “June Gloom’, especially along our coastal stretch of gardens.”

The mild temperatures and overcast of this year have extended the spring blooms several weeks more than usual.  The long show of flowers has been one of the most memorable in many years. Nonetheless, summer is bearing down on our gardens.  Temperatures, both day and night are rising noticeably, daylight hours are lengthening each day and the sun is high in the sky. Water now becomes the most important ingredient of your garden.

Automatic sprinklers need to be reviewed this month.  Start by manually turning on each of the stations and checking carefully the all of the heads are working correctly, delivering water as evenly as possible.  Next, adjust the duration of each station’s watering cycle.  Finally, decide on the frequency that each cycle should activate and the time of the day.

Regardless of how precise your underground sprinklers, drip emitters or other automated system might appear, no system delivers water perfectly.  A good gardener knows that there will always be pockets within the garden that need individual attention.  Although usually watered by hand, in my experience, potted containers are where watering mistakes invariably advertise themselves first.

Plants that originated in any of the worlds Mediterranean climate areas, such as most of our California natives, have a well evolved response to the warm, long, dry days that lie ahead.  They slow down or stop growing.  They retain their leaves, but are nearly dormant otherwise. Common examples are lavender, rosemary, native salvias, and olive trees.  These plants desire far less summer water and fertilizer than most of us realize.

A second group of plants are those that come to us via the worlds sub-tropical or tropical regions.  These plants are usually easily recognized and include hibiscus, impatiens, citrus, philodendron, plumeria, banana and many more.  These equatorial plants revel in the long days, steamy nights and warm days of summer. They pout during the cool winter months.  However, in our Orange County’s thoroughly Mediterranean climate these tropicals also depend upon regular applications of water and nutrients during the summer.

Summer annuals and vegetables should mostly be planted by now, but along the coast you can still add heat lovers like zinnias, dahlias, lisianthus, verbena, celosia, coleus, begonias, impatiens, corn, beans, squash, melons, peppers, tomatoes and basil.

Coastal gardeners, because of their milder temperatures, can still nurse a few more flowers out of springtime perennials like delphiniums and foxglove.  But don’t be tricked, the next few months are really the domain of heat lovers like pentas, gaillardia, gloriosa, perennial dahlias, and tuberous begonias.  If these aren’t represented well in your summer garden, June gloom allows an opportunity to plant a few of these and still have a show this summer.

As you tend to your June garden keep an eye out for pests that are active at this time of year, keeping in mind that treatment isn’t always necessary.  Snails and slugs may still be common, especially if you are watering too often.  Rose slug, the little critter that eats all those holes in the leaves of your roses, is abundant in June (control them with the organic product, Spinosad).

Of course, I cannot let June slip by without again mentioning my favorite garden topic, soil.  Dull and uninteresting as it may appear, it is the lifeblood of a good, healthy and sustainable garden.  All good gardeners eventually figure this out, although for some it comes toward the end of their gardening careers, after years of unneeded expense and struggle.

The best present you can give your June garden is a fresh, thick layer of rich, organic compost or mulch.  Applied now, just before the hottest months, it will cool the soil, reduce irrigations, suppress weeds, improve soil structure and best of all, feed the invisible soil life that is working to sustain the health of your plants.  Over the past two weeks I’ve spread 18 bags in my garden and I’m still not done!

An interesting gardening year has unraveled so far.  January and, February brought sunshine and warmth, March and April had showers and chill, May had gray and now it’s June gloom.  I haven’t seen our local gardens and flowers this beautiful in years.  I hope that includes yours.  What will summer have in store for us?

Ron Vanderhoff is the Nursery Manager at Roger’s Gardens, Corona del Mar