Pelargonium, Part 2

Last week, I wrote about the confusing situation of Pelargonium and Geranium. If you missed that one, click here. There was too much information to include in one post, so here is the rest.

Pelargoniums, commonly called Geraniums, are grouped in categories, based on certain characteristics. I found conflicting information about these categories, but there are 4 groups that everyone seems to agree on. Those are Zonal, Ivy-Leaf, Regal and Scented Leaf.

Zonal Geranium
The most common type, these are found in gardens across the country. The name Zonal is said to be based on the darker zone of color that often forms a band of color on the leaves. It was used to separate cutting-grown plants from seed-grown plants. Apparently, in the past, seed-grown plants were not that great, and did not have the dark zone on the leaves. Today, seed-grown plants have improved, and each method accounts for about half the plants. Plus, you can buy plants with tri-color leaves, or variegated markings.  Flowers are most popularly red, but also come in pink, white, salmon and bicolor. The flower clusters are held above the foliage on long stems. They are mostly scentless, and have thick, succulent stems and fuzzy leaves. Years ago, people would dig them up, knock off the dirt, and hang them under the house for the winter. Now, we have heated and lighted basements, so that does not work as well.

Ivy Leaf Geraniums
You probably won’t be surprised to learn that these Geraniums have leaves that resemble the shape of ivy leaves. They also have a vine-like growing habit, so they work great in hanging baskets and containers. Leaves are smooth and leathery, and they can grow 3 feet high and 4 feet wide in one season. Flowers colors are less intense than the zonal geraniums, and the flower clusters are smaller, and less dense. Blooms appear from mid-summer to late fall and can be white, pink, red, lavender or magenta. These are also called Cascading Geraniums.

Regal Geraniums
Also known as Martha Washington, or French, these have large, frilly flowers in white, pink, salmon and purple in many different combinations. Growing 2-4 feet tall, they have woody stems, and stiff leaves. Unlike the other varieties, Regal Geraniums may require shade in the afternoon. They dislike intense heat and humidity and do well in cooler, northern areas. These bloom in late spring and summer, and will probably need more water than the other types, along with regular fertilizing. To keep these indoors through the winter, they must be brought indoors before there is any danger of frost.

Scented Leaf Geraniums
Once again, the special feature of this plant is fairly obvious from the name. This group includes a wide variety, with many different foliage types and habits. Leaves can resemble oak leaves, or be soft and finely cut. The one thing they have in common is that the leaves are scented.  The flowers are not the main attraction here, and they are smaller and less showy than other types. To take advantage of the scent, plant scented leaf geraniums indoors or in a sunny area near the patio. Scent rises when the leaves are in the sun, or when you touch them. Don’t overwater them, and take them indoors for the winter. Scented leaves can be used to flavor baked goods or teas, or used in sachets and potpourris. There are a lot of scents available, including apple, peppermint, apricot, nutmeg, strawberry, lime, orange, ginger and coconut. Some are used in perfume, with the rose scent being the most valuable commercially.

Pelargonium

If you’re thinking that the flower pictured above is a Geranium, you would be partly correct. Geraniums, as most of us know them, are one of the most popular flowering plants. Easy to grow, requiring little care, they add a bright spot of color to any garden. The confusing part is that scientifically, they are not Geraniums.

As with most things, it all starts with Carolus Linneaus, the man who invented the classification system for all living things. A large group of flowering plants native to South Africa was placed in the genus Geranium, in the family Geraniaceae. The flowers grew popular and were exported to many other countries, and were called Geraniums. Later, around 1789, someone realized that the flowers in that genus had major differences, and the genus was split into 4 or 5 separate genera. One continued to be called Geranium and another was named Pelargonium. I won’t go into the others, it will just confuse matters.

Geranium, the genus, contains species of hardy perennials and native wildflowers, commonly called Cranesbills. The flowers have 5 matching petals, evenly spaced. The Geraniums we know were placed in the new genus, Pelargonium. The problem was that people were already accustomed to calling these plants Geraniums. Though they officially became Pelargoniums, people refused to call them that, and stubbornly call them Geraniums, even today. To tell them apart, some say the plants in the Geranium genus are “True” Geraniums. The Pelargoniums are also called Storksbills. Sound confusing? I thought so.

Pelargoniums are very tolerant of heat and drought. In warm areas, such as zone 8 and above, they are perennials.  Here in Michigan, as in a large part of the country, they are grown as annuals. Single Pelargoniums have 5 petals also, but the upper 2 are often different in size, color or markings from the other 3 petals. Some of them are scented, but some of the scents are not pleasing to humans.  There are about 200 species of Pelargonium, but only about 20 have been used to develop the thousands of cultivars available today. Some of them are sought out for their foliage, rather than the blooms. Leaves can be velvet-textured, leathery, marked, variegated and scented.

In the garden, they prefer full sun, well drained soil and temperatures that would be comfortable to people, around 55-75 degrees. If it gets too hot or too cold, they stop producing flowers. Otherwise, most of them bloom much of the summer.  They work well in almost any situation, hanging baskets, window boxes and containers, as well as directly in the garden. Too much water, or sitting in water will cause the plant to turn yellow and possibly die. Spent flowers should be removed, as should any dry or discolored leaves. Pelargoniums like to be fertilized regularly, they are heavy feeders. Propagation is by stem cuttings, root divisions, leaf cuttings or seed. As usual, growing from seed is not always reliable.

Pelargoniums can be wintered indoors in cooler climates. Back before we had basements that were lighted and heated, you could just hang the plants from the ceiling after digging them out and knocking off the dirt. In order to do that, it must be dark, dry and cool, about 45-50 degrees.  I have several plants in containers, and I just bring them into the house before the first frost. I cut them back somewhat, and place them in a sunny window. Some of these plants have been around for several years now.