They are commonly called geraniums, although in reality, although belonging to the geraniaceae family, their botanical name is Pelargonium; these are semi-evergreen shrubs, originating in Africa, cultivated in Europe for a long time, as decorative plants, but also as medicinal plants.
Of simple cultivation and with abundant flowering, geraniums find space on terraces and balconies, although in many regions, where the climate is mild, they can easily be grown in the open ground; in fact these plants can easily withstand temperatures even close to 4-5 ° C, as long as the soil in which they are grown is very dry.
The most commonly used varieties are hybrids, which can be divided into two large groups:
- Pelargonium zonale: with pelosette leaves, erect stem and large flowers gathered in almost spherical umbels. Said zonal due to the darker zoning easily found in the center of the leaves.
- Pelargonium peltatum: the so-called geranium ivy, with long twining and elastic stems, with creeping or hanging growth, and flowers smaller than the previous one.
In the nursery are now available various species and hybrids of geranium, the most common is the pelargonium macrantha, or imperial geranium, with large flowers with bright colors and jagged foliage, much appreciated for its dense and compact development.
There are then numerous hybrids and cultivars, with perfumed foliage, with flowers of particular color, or with bizarre-shaped petals; impressive growth geraniums, other dwarfs, which remain below 20 cm in height. And finally we can find botanical geraniums, more delicate and less showy plants, but certainly very beautiful; the pelargonium species are about 250, almost all with fleshy stems, some completely succulent, with foliage of various sizes, some very fragrant; often the botanical species have small flowers of a pinkish color, much less showy than those of the hybrid species; however, these plants often have peculiar characteristics that make them pleasant to cultivate, such as succulence, or foliage with a penetrating aroma.
How to grow geraniums
As said before these plants are easy to cultivate, maybe even for this reason they find place on terraces and balconies.
The first rule to follow in order to obtain beautiful geraniums rich in flowers concerns the vases: let's avoid placing our geraniums in excessively large containers, otherwise we will find ourselves with lots of leaves and very few flowers. In fact, if the pelargonium finds a lot of space, it tends to produce enormous root systems, followed by lots of vegetation, and few flowers.
So we choose a vase that is not too large, but not even tiny; for a couple of geranium ivy plants we can choose a small planter, 40-50 cm wide, about 20-30 cm deep; for a single well-developed zonal geranium, a bell-shaped vase of 20-25 cm in diameter may suffice.
In the jar we place a good universal soil, rich and soft, and a handful of slow release granular fertilizer, which will guarantee the right level of mineral salts in the soil for about 3-4 months. If we do not like to use the slow release fertilizer, remember to fertilize our plants every week, with a good fertilizer for flowering plants, used in half dose compared to the one recommended on the package; the fertilizations will be regular from March to September, we suspend them in autumn and winter.
We place our geraniums in a sunny place, which possibly does not receive an excessive number of hours of direct sunlight per day, they can be enough 4-6 hours; we avoid the southern positions, where the plant receives the sun for the whole day, because summer heat could ruin the plants in the long run.
During the growing season, from March to September, we water the plants every time the soil is dry; although these plants resist without short periods of drought, we avoid leaving them dry too long; we also avoid leaving the soil moist for prolonged periods of time: when in doubt, it is better to water once more than drown the plants.
Periodically we remove the withered flowers and leaves that naturally dry out, to prevent them from being vehicles of fungal infections. In addition to preventing disease, this practice constantly gives us a healthy and beautiful plant.
During the winter
The geranium plants are not annual, they can be grown from year to year, provided you have the place to shelter them if in the area where we live the winter is rigid. To preserve our geraniums it is fundamental first of all to avoid watering them excessively in autumn, and above all to suspend the fertilizations, so as to favor the entry of the plant in a period of vegetative rest; at this point we place our geraniums in a place where they do not receive watering, and where they can be protected from frost.
Anyone who can afford a cold greenhouse will surely have no problems; those who are forced to keep the vases on the terrace can protect them by leaning them against the wall of the house, and covering them with woven fabric.
Until the autumn and winter climate remains mild it is good to sporadically water the plants; when we have temperatures below 2-3 ° C we suspend watering.
Over the years, geraniums tend to form little compact shrubs, and often empty of branches and leaves in the lower part. For this reason, at the end of winter, it is good to drastically prune the plants, so as to favor the development of new shoots even in the lower part of the plant.
With the arrival of heat then, we prune the plants, extract them from the pots and change all the soil with new, fresh and rich substrate. We will then resume watering and fertilizing.
Geranium - Pelargonium: From a geranium many geraniums
Pelargoniums maintain herbaceous, round and fleshy stems over time; as with succulents, these stems tend to root very easily. We can use this characteristic of geraniums to practice numerous cuttings, especially when, at the end of winter, we prune the plants of the previous year. In reality this is what happens in the nursery: in general the pelargonium plants that are sold in spring are cuttings, prepared in autumn or winter in greenhouses, of the plants of the previous year. "Old" plants are often called "mother plants", since they have "spawned" many daughter plants.
To produce pelargonium cuttings it is sufficient to remove branches, even thin ones, using a well sharpened and clean knife; the branch can be cut into 10-15 cm long portions, from which the leaves are raised in the lower part, which is cut obliquely, so that it exposes as much surface as possible to the air. The cutting is immersed in the rooting hormone and then it is placed in a good soil, mixed with sand, slightly damp. The cuttings so practiced are cultivated in a warm place and again, remembering to never leave the ground dry for prolonged periods of time.
If we have a cold greenhouse where we can put the geraniums we can prepare the cuttings already in late summer; if we do not have this luck, we will have to prepare the cuttings in early spring; usually 20-25 days are enough to get a small plant, which will quickly develop new leaves and new flowers.