Twelve Hours of Summer Sun

Just how much heat and sun can a plant handle? Most gardeners define "full sun" as six hours or more of sunshine. My garden easily receives twelve hours of full sun in the summer. The temperature exceeded 100°F recently. Our heat index has been well over 100° on several days. We've had no significant rain in weeks while the 90°+ temperatures have pounded the garden and the gardeners.

My garden is filled with plants that can handle tough heat, but even camels eventually need a drink in the desert. It was time.

I had to water the garden last evening to prevent a meltdown! We do have a deep well. Still, I don't like to water the garden and I really don't like to water a garden in the evening—but, I wanted the water to soak into the soil instead of evaporate in the morning sun.

My husband said "you can almost hear the sigh of relief from the garden."

This morning, I rushed out at 6:30 am, hopeful for a recovery. It was hot. Too hot. I was glad that I hadn't waited until morning to water the garden because I couldn't handle the heat!

My camera lens had to clear up as it was fogged by the transition from air conditioned comfort into the inferno.

The garden put on a perky face for me. All was well—at least on the surface. The soil is still very dry, but my thorough watering revived the garden for a few days.

So, which plants performed best in this unplanned trial of dry, hot torture?

Salvia guaranitica 'Black & Blue' with wide, bright green leaves was definitely looking sad. A little water did the trick and all the plants were back to normal all day today. Salvia 'May Night', 'Caradonna', 'Marcus' and 'Sensation Rose' were fine. Salvia greggii, in all colors, looked totally undaunted by the heat.

The new varieties—salvia chamaedryoides and salvia pachyphylla—were especially pleased with the dry conditions and hot temperatures, so I carefully avoided giving those two any water at all! Sounds cruel, but I won't mess with happy plants!

Most agastache varieties were real troopers, but 'Golden Jubilee' with wide, light green leaves really had to be watered. The big surprise was that the companion to drumstick allium, agastache 'Cotton Candy' (pictured above) needed no water. 'Cotton Candy' was added in September 2009 and has been blooming since April. If it continues to perform well, it is going to move into first place as my favorite agastache.

The buddleia leaves have drooped during the heat of the day, but each morning (so far), they have looked fine. No extra water has been given, but that may change as we expect another 100° day on Sunday.

The coneflowers, ageratum, joe pye weed, ironweed and daylilies needed water. I lost a few volunteer tall garden phlox planted beside the stone walk inside the cottage garden. Other patches of phlox, planted among other perennials, are fine. Sedum were fine. A few lamb's ear plants were suffering, but the older ones are doing great.

Gaillardia, lavender, ornamental grasses, flax, Russian sage, santolina, verbena and all of the coreopsis varieties were fine before the watering. I'm not sure they appreciated my efforts to drag several hundred feet of garden hose around the garden. The drip irrigation has never been extended to the drought-loving plants.

Another plant that has received no supplemental watering must have a tap root long enough to reach down to the water table. Perennial heliotrope 'Azure Skies' (that blooms six months) is simply amazing! It has been an edger in the cottage garden, and I started adding it along the edge of the outer gardens. Although all of the heliotrope in the south garden was planted since April, it is blooming like crazy, loving the heat and untouched by deer.

When I finished the watering chore (2 1/2 hours), I took on another chore last evening and worked until the moon was up.

As difficult as it was to endure the heat myself, I decided it was much better than working in the sun. I deadheaded as many spent flowers as possible, as well as cutting a few nice blooms to bring inside to enjoy. In times of little rain, I try to make an extra effort to deadhead to hopefully reduce stress on the plant.

It is these trials by nature that test both the garden and the gardener.

Words and photos by Freda Cameron, Defining Your Home, Garden and Travel. Deer and rabbit resistance varies based upon the animal population and availability of food. All company or product or patented names mentioned are registered trademarks, copyrights, or patents owned by those respective companies or persons.