Although frangipanis are fairly hardy, there are some pests and illnesses which may affect them, predominantly fungus, scale, frangipani rust and stem rot.
Fungus, Mold & Powdery Mildew
Leaves affected by fungus or mould may be sprayed with a copper primarily based fungicide and white oil solution. In the event you choose organic options, attempt a combination of powdered milk powder and white oil or detergent.
Holding plants well nourished helps prevent fungal infections. Potash is especially good for bettering illness resistance in frangipanis.
Leaves affected by hemispherical scale have darkish to mild brown bumps which might be glossy, clean and hemispherical. Leaves could have a black sooty coating.
Scale will be handled by spraying with white oil in spring to early summer time. If you happen to desire organic options, strive encouraging natural predators to your backyard, similar to ladybugs, the scale eating caterpillar, and parasitic wasps. Many crops appeal to ladybugs together with daisies, zinnias, and zucchini.
There's a new disease attacking frangipanis in Australia called frangipani rust. It is most noticeable in late summer and early autumn. An orange to yellow powdery substance (truly pustules) appears on the underside of leaves. They rupture and unfold spores which pass the illness to other vegetation close by. The higher sides of the leaves are brown and discoloured. Extreme infections may trigger the leaves to drop prematurely and can lead to the dying of small crops, nonetheless bigger trees appear to undergo no unwell effects (apart from leaf drop).
To manage frangipani rust try utilizing a fungicide (such as Mancozeb) in the warmer months to slow the event of the illness. Disposing of all fallen leaves in winter and spraying the tree and the world beneath the tree with a fungicide may gradual the reappearance of frangipani rust next season.
The good news is that lately some frangipani bushes have built up a resistance to rust, so it might be on it's way out.
Stem Rot & Black Tip Dieback
As frangipanis lose their leaves over winter, tender, withered stems might turn into visible. It is a condition called ?stem rot' and it's fairly common in bushes that have been stressed by frosts, drought, lack of daylight or simply plain previous age.
The best way to keep it underneath management is to easily prune off any diseased development, however while you do, it's necessary to be sure you lower it right back to good, healthy tissue.
Dying tip growth is usually referred to as black tip dieback. Some newer deciduous cultivars and evergreen frangipanis are significantly susceptible to the illness.
Industrial frangipani growers suggest the problem is worse in areas the place fruit-spotting bug and beetle exercise is excessive. It is because any insect attack on the tip of the plant predisposes it to a secondary dieback infection.
Affected crops usually reshoot beneath the damaged portion of stem. If crops appear unpleasant or you might be involved that the rot is advancing down the stem, use sharp pruners to cut again to clean tissue. You'll want to use sizzling water or family disinfectant to clean pruners between cuts so as to minimise potential disease transfer.
Badly affected vegetation could profit from an application of fungicide to limit the disease's unfold.