Anyone who takes up growing fuchsias will run into most of the following at some time or other. The problem is that insecticides and fungicides that were readily available to the public are fast disappearing. I have to add that any products I may recommend, you use to the manufacturers recommendation and I take no responsibility for their misuse. Prevention is better than a cure and I start spraying early in the season whether the plants need it or not.
Lets kick off with good old whitefly. It looks exactly as is named, tiny flies that flitter about when disturbed then settle on the underneath side of leaves. This is where their activity takes place, tapping into the leaves extracting nutrients especially sugar. They excrete Honeydew which drops onto lower leaves which then plays host to Sooty Mould. This is where picking up plants when watering comes in. The whitefly will fly off at the slightest disturbance. A minor attack can be controlled with finger and thumb, but if left to become an infestation they can seriously weaken plants. Spray with Provado Ultimate Bug Killer. This is a systemic which is taken up by the plants and helps towards control. If you are against using insecticides then a tiny drop of washing up liquid in a 1litre fine sprayer will suffocate the adults but will not kill the eggs. Spray every 3 days to break the life cycle.
Aphids are also known as greenfly and blackfly. They are sap sucking insects and easier to spot than whitefly. I have never seen blackfly on fuchsias but greenfly seem to colonise on flower buds when they are starting to mature and would seriously damage the flower if left. They also damage the very growing tips and I generally find them on the hardy fuchsias in the garden as soon as early spring and if left would stunt the growth so much as to delay flowering or the plant not to flower at all. Usually the damage is done before you spot it. Conifers are renowned for harbouring aphids.I use Rose Clear 3 and, again, spray before any signs of damage as a preventative.
Red Spider Mites reside on the underneath side of leaves and are almost invisible to the naked eye. They can be identified, through a magnifying glass, by two dots on their back. Damage to a plant is made by the infants chewing away at the leaves which turn a mottled colour, dry up and drop. A plant can be devastated in no time. The adults spin fine webs over the plant, again hard to see until you spray with a fine mist of water. They will move from plant to plant by walking or using the fine web for an air assault. Damage is done before you realise it and can be the exhibitors nightmare. They thrive in hot dry conditions, another reason for fuchsias to be out of the greenhouse in Summer. I have too many to do that so I have solid staging covered in capillary matting which is covered with fine grit. This is kept wet during hot spells to try and reduce the temperature and increase humidity. One has to be very vigilant to spot the first signs and you could try a weeklytreatment with S.B. Plant Invigorator which is a plant stimulant and pest control, or try Bayer Organic Pest Control (B&Q)
Now we come to what I believe to be the fuchsia growers favourite pest. Mention it to a fellow fuchsia grower and a smile comes across their face. I think we have all faced this adversary at sometime or other.The adult Vine Weevil is about 10mm long (excluding it’s feelers) and is not to be confused with the ground beetle which is longer and flatter. They are nocturnal and rarely seen during the day. They have hooks on their feet which allows them to walk upside down on glass and drop into hanging pots suspended from the greenhouse roof - I kid you not! The adult does not do a great deal of damage except from cutting crescent shaped notches in leaves, which serves well as a warning sign. They lay eggs just under the surface of the compost and are often mistaken for the granular type plant food or vica versa. The eggs hatch into grubs about 10mm long and burrow their way down into the compost and start feeding on the fine roots. That’s were the damage begins. In a bad attack a plant will wilt and can be mistaken for in need of watering, then the plant collapses completely and if pulled out of the pot will have little or no roots at all.Vine Weevils are very clever insects and always seem to target plants which they know will have fine roots, such as young fuchsia plants. I know they are in our garden, but they don’t bother the hardy fuchsias, the roots are too old and tough for the grubs. Its usually pot and container grown plants with fine compost they go for.Treatment is fairly easy now with the introduction of Provado Vine Weevil Killer 2. This is applied as a root drench every six weeks to pots and containers and will kill the grubs. Again I will do this as a preventative as it’s also useful for controlling greenfly and whitefly. I stand the pots in saucers whilst being soaked and any surplus that runs through is re-used on the next plant. Any adults found go under the boot with a satisfying crunch.
Fuchsia rust is a disease caused by a fungus, Pucciniastrum Epilobii, that spreads by airborne spores and by hand after handling infected leaves. Rust will not kill a plant but will make it look very unsightly and it would certainly not be eligible to enter a show.First signs are yellow circular patches appearing on the upper part of the leaf with the corresponding orange coloured pustules underneath. If left untreated the whole leaf would shrivel and other leaves become infected. In mild cases, removal and disposal of infected leaves may be enough. In severe cases spray the underneath of the leaves with Rose Clear 3. In either case isolate the plant until cured.
Botrytis shows itself as a grey mould on stems and foliage, usually starting at the base of the stem and working it’s way up until the stem turns brown, becomes very thin and then collapses taking with it any growth attached to it. Botrytis can be avoided in the first place by allowing plenty of air circulation around the plants even removing lower leaves to help. Careful watering will help, allow the plant to almost dry out and then water instead of keeping the compost waterlogged. Once plants are established in pots water from the bottom if possible.No fungicides are approved for use against Botrytis but some fungicides to control other disease may have some control but not guaranteed.I get the odd plant losing one stem so I don’t bother spraying with anything, I just try and follow my own recommendations!
Fuchsia Gall Mite. This is one pest that I hope you never come across. It was first discovered in Brazil in the 1970’s and has since spread to California, France, Germany and the Channel Islands. It spread to mainland Britain in 2007 where it was found on previously healthy hardy fuchsias near Fareham, Hants. Since then it has been found in gardens in Middlesex, Kent & Devon (as at July 2011)The mites are too small to be seen without a microscope and they infest the shoot tips where they suck sap and excrete chemicals. An infestation leads to the distortion of growth and buds. Removing the infested growth will remove many mites but new growth is likely to be infested. Pesticides available to the home gardener are ineffective.The only choice is to cut off and burn the infected branches or if needed the whole plant.