By Norman Winter
MSU Horticulturist
Central Mississippi Research & Extension Center

Many of us who live in Mississippi’s heat have wished for geraniums with blooms as tough as our summers, and we finally have Caliente and Calliope to make life more enjoyable.

Each year when I visit the big flower trials in California, I drive from San Diego to San Jose. I get green with envy seeing the ivy geraniums growing almost like weeds along the more than 700 miles I travel between these cities.

Now we in Mississippi can enjoy Caliente and Calliope, two unbelievably ivy-zonal hybrid geraniums. This new genetic material has given gardeners a reason to fall in love with the geranium all over again.

In our Mississippi trials, the Caliente ran circles around the competition. Not only did it do better than other geraniums, it also beat out several other hot summer survivors. University of Georgia trials showed similar results. Caliente has “winner” written all over it.

The Dallas Arboretum has some of the most well-known and rigorous trials in the country. Calliope was outstanding, blooming there until September.

The Caliente series boasts eight colors, and Hot Coral, Orange and Pink are the newest in the line. Calliope garnered all of its attention from Dark Red but is now also available in Scarlet Fire.

Let me qualify some of these glowing compliments. In this part of the country, we will probably have more success using them as container plants, where they truly can provide the “wow” factor. They are such standout performers that you can forget the “thriller, spiller, filler” recipe and let them perform their magic alone.

Of course they will work as component plants, too. I have some in mixed planters with scaevola and some great new ornamental sweet potatoes.

I like these geraniums in containers because they are movable. We can give them full sun during spring and early summer, and then adjust them to morning sun and afternoon shade or high, shifting light. Another reason they work well in containers is that their ivy habit is somewhat spreading, allowing their true beauty to be enjoyed in containers, baskets and window boxes.

But they can also work well in the landscape. The ideal Mississippi location would be full sun until just past noon, then a little protection in afternoon shade. They will perform when not planted in tight, compacted clay. To prepare your soil, loosen it 8 to 12 inches deep, add 2 to 3 inches of organic matter, add one pound of 12-6-6-fertilizer per 100 square feet, and then rake the soil smooth.

Geraniums are heavy feeders, and many gardeners do not apply enough fertilizer to meet the plants' nutrient needs. Feed them with a dilute, water-soluble fertilizer like a 20-20-20 every two weeks or with a granular, controlled-released fertilizer every four to six weeks. When it is time to deadhead old flowers, don't just clip the cluster. Pinch or break off the flower stalk at the base.

As you continue to shop for plants and you see geraniums that have a little of that ivy habit, see if they might be Caliente or Calliope. Take these home with you, and you’ll know you are getting a plant that will bring lots of color and enjoyment, even when you plant it in early summer.