Brightly coloured geraniums
Published 22/05/2016 | 02:30
Ever-popular, there are benches full of colourful geraniums for sale in garden centres at the moment. Whether grown in pots, in flower beds or as house plants, this is one of the most versatile of flowers and it is easy to grow. They are native to South Africa, where there are many wild kinds, but they are not hardy outdoors, which is why it is not wise to plant them outdoors until the end of May, or a bit earlier, in a mild area.
The great value of the red geraniums is that they keep on flowering from early summer to late autumn. Although often treated as once-off bedding plants, these geraniums are actually long-lived sub-shrubs - not quite shrubs, as they do not make any real wood in their stems, but still woody enough to make low bushy plants if grown for several years.
When grown as house plants, they can be quite easily allowed to grow as a large bushy plant, if desired, because they can be grown indoors for years without frost damage. Red geraniums are still planted in public parks and private gardens as bedding plants, but the use of pots, window boxes and baskets has greatly increased and geraniums are excellent for this purpose. Their fleshy stems and thick leaves give them a natural ability to withstand drought - always a good quality in a plant grown in a container.
The most common form of red geranium, or pelargonium, used is the zonal pelargonium. This gets its name from the banded zones of brown on the leaves of some kinds. The leaves are rounded and broad and the flower heads are tight, ball-shaped and about 15cm across. As the stems grow, new flower buds are produced from the top. There are two other related groups: regal pelargoniums and ivy-leaved pelargoniums.
The regal pelargoniums are great in pots and ideal as greenhouse plants or house plants in a warm porch or conservatory, where they benefit from extra sun-heat. They tend to flower in a huge show in early summer and to a lesser extent afterwards, so they are not great for bedding purposes. Ivy-leaved pelargonium has ivy-shaped fleshy leaves and this trailing or climbing type is often used in baskets and window boxes, trailing down in sheets of colour. It looks great in a conservatory, trained on trellis. Ivy-leaved kinds can survive outside in the mildest gardens with a warm wall at their back.
Feed and water generously in early summer, then ease off on both. Always use a high potash liquid feed, such as tomato feed, to encourage flowers. Too much feeding produces lots of leaves at the expense of flowers, but inadequate feeding leaves the plants looking scrawny. So keep on feeding and watering right through summer to keep the plants going, without over-doing it.
Q: I have a new lawn only three years old and lately it has being covered with scutch grass, can I add anything or spray anything to get rid of it? V Carey, Co Cork
A: What you are seeing, that looks strawy and like scutch grass, is just the flower stems beginning to shoot out. You need to mow more often and a bit tighter to catch these stems which are produced mainly in early summer and are not so evident later.
Send your questions to firstname.lastname@example.org. Questions can only be answered on this page.