Early flowers and wet weather
Published 03/01/2016 | 02:30
Well before the end of the old year, there were many reports from around the country of plants in flower unseasonably: daffodils, snowdrops, cherries, rhododendrons, roses and camellia. Also lupins, delphiniums, witch hazel and sweet pea were seen flowering in late autumn. In some places, birds have been singing at night, confused by relatively warm air and bright street lights.
The winter has also been one of the wettest ever, with rainfall in most parts of the country 50pc or more above average. The ground has become saturated and no longer has any capacity to hold water, so water runs off. The two phenomena are connected. Winds from the south or southwest bring warm air, which is moisture-laden, and when this air meets colder air from the north, the water vapour condenses and falls as rain, hail or snow.
The plants responding to the unusually warm weather that has occurred in autumn and winter can be placed in two groups. One group are late flowers on summer- and autumn-flowering plants, such as roses, lupins, delphiniums and sweet pea. There were ripe fruits on raspberries, though insipid, in the first week of December.
These plants were simply taking advantage of the relatively high temperatures. For the same reason, leaf-fall on deciduous trees came rather later than usual, by more than a week or so, and autumn colour at leaf-fall was good.
Lupins and delphiniums are soft, fast-growing plants that often throw up a few late flowers but in a cold autumn, there will be no sign of them. Rubeckias, too, went on forever this autumn.
Roses are great for flowering late in a mild year, often up to the New Year, and it is not all that unusual to have a few flowers good enough to cut for indoor use at the end of the year. Some varieties are more likely to have late flowers, such as 'Alberic Barbier', which has pale yellow flowers and often holds a good proportion of its foliage through winter.
The other group of plants flowering out of season is spring-flowering kinds that are tricked into flowering early by mild winter weather.
This group includes snowdrops, daffodils, camellias, cherries and rhododendrons.
Most of this group come from areas of the world where the seasons are more predictable, one week it is winter, next it is spring. In Ireland, it can be balmy in winter and produce frost in August. No wonder that the non-native plants are fooled.
Most of the plants that respond quickly to warming weather have a propensity for early flowering in any case. There are varieties of snowdrop that flower every year as early as October and a daffodil variety called 'Rijnfeld's Early Sensation', regularly flowers in January, and earlier in a mild year. So it is not too surprising when these bulbs flower early, but the extent to which they have done so this winter is truly exceptional.
Camellia, witch hazel and early rhododendron species are early to flower normally but they are quicker off the mark if the autumn weather is mild. Some camellias flower in November most years, but others have done so this year.
The rhododendron variety 'Christmas Cheer' sometimes misses its name-date but not this year when it has outdone itself.
Equally, the winter-flowering cherry has been exceptional this year.
The Chinese witch hazel normally flowers in January, but was flowering before the leaves fell in some cases.
Generally, these early flowers fall back into line as the seasons level out.