DURING the past week, two friends have telephoned about their latest gardening woes.
The first had just discovered that a large clump of aloes had been killed by aloe snout weevils ‘Scyphophorus acupunctatus,’ a new-problem-in- Spain-insect that has taken about three years to arrive on the Costa Blanca from the Costa de la Luz.
Unfortunately, like the palm weevil, there is no really effective treatment for diseased plants.
The insects are brownish and 15 to 30 centimetres in length.
The second friend had just discovered that both their tall specimen Phoenix palms had succumbed to the red palm weevil ‘Rhynchophorus ferrugineus’ in spite of being treated, so a crane lorry will arrive shortly to cut them down and remove them.
This weevil is also a type of snout weevil but can be 30 to 50 millimetres long.
I am not aware of how the aloe weevil came to Spain but the palm weevil is said to have been imported into Andalucia in 1994 in a batch of diseased palm trees.
By 2006, the flying weevils had spread to France.
Although destroying the tropical image of the coastline, village squares and gardens, it has not been the most damaging problem to Spain’s floral image.
That spot must be taken by the African Geranium moths ‘Cacyreus marshalli,’ or ‘Tespis Tespis,’ which arrived in the early 1990s, apparently in a lorry load of geraniums from a Dutch greenhouse.
Again it took just a few years to spread along the costas and then inland.
Gone now are the large banks of cascading geraniums and apartment-covered geraniums that last for a decade or more.
Even planting garlic segments in geranium pots and spraying twice a week with a spray is not a total solution, for abandoned plants in absentee owner gardens and apartments can be a virulant breeding ground.
Other pests that have become a bother during the past 25 years are the Cirtus minero moth and the many fruit flies attacking citrus and other fruit trees, tuti flies attacking tomatoes and many other fly-type insects attacking vegetables.
I have just read an interesting research paper about citrus pests of importance to the Spanish citrus industry where markets like no blemishes on the skins and any attacks to leaves and flowers can reduce the productivity of trees.
The paper reported that for the past 45 years there has been a new imported insect pest every three years with eight in just the past 10 years.
From our experience the best thing that expat amateur gardeners can do is to spray fruit trees and diseased vegetable plants regularly with neem oil solutions in water.
© Dick Handscombe www.gardenspain.com September 2014