Pests of roses

Pests of roses

Question: Rose pests


Good morning, I need help to defeat a disease that my roses unfortunately suffer from years: it is a small animal that empties the stem and causes the loss of flowering; I have had this problem for years now and I can't get rid of them ... plus last year I found the same problem on geraniums and surfinie! I have been to the consortium and the only solution they have found is a granular insecticide for terrestrial insects. last year I proceeded to remove the affected apices, I burned everything to avoid contagion, I gave the insecticide for terrestrial insects, I did the treatment with decis and with confidor for the cochineal and aphids as well as the classic verdigris for mushrooms ... I would like to avoid having to repeat the die, and finally have a flowering in peace! what to do then? could you give me some advice? precise that I am not really inclined to natural methods alone.
thank you very much!

Answer: Rose pests


Dear Ross,
the problems that afflict your plants, roses and geraniums are different: roses are attacked by an insect that is called a rose fly, in fact it is a tiny wasp, which loves to lay its eggs on the stems of roses; from the eggs the larvae are introduced into the stems and feed on the inside of the stems, leaving them hollow, with obvious damage to the vegetation; the geraniums of geraniums are instead a fairly “new” parasite, arrived in recent years from Africa: the larvae eat leaves and stems, then enter the stems and lay eggs, and then flicker away as adults; if you keep the geraniums from one year to another the new larvae will eat whole plants in a short time. The products that you commonly use on your plants do not work with caterpillars, especially if they are holed up inside the stems of your plants. Confidor (based on imidaclopryd) is a broad-spectrum insecticide, to be used with great caution because it kills everything it finds (including bees and other useful insects); it works very well against aphids, has been specially invented to eradicate them, and should be used when there are no flowers in the garden. The decis is a common insecticide based on pyrethrins, which has a killing function, that is, it kills all the insects on which it is sprayed. Clearly the action of these insecticides is not useful against bruchetti and larvae of defoliating insects. To eradicate rose flies, the best method is to remove all the damaged branches and burn them, so as to kill an entire generation and prevent it from spawning. Probably a foliar absorption insecticide could then do the rest of the work, making the leaves uninteresting for any new adults that may be passing through your garden. Against the caterpillars of geraniums, also here, it is necessary to use an insecticide that penetrates into the tissues of plants, in order to kill all insects; since your geraniums are in pots, you can try to use the confidor mixed with the water of the watering, so that it enters the tissues of the geraniums, or you can try with the insecticide tablets found in the nursery: they are inserted into the soil, and every time you water it dissolves slightly, and then the plant remains protected against insects for a long time. These remedies must obviously be used only for potted plants, because if used in the open ground they would kill a series of useful insects present in the soil. Many useful insects help us contain the populations of harmful insects, killing them all with broad-spectrum products, or using insecticides indiscriminately, the end result is that our plants lose some of their natural defenses.