The wild beauty and sweetly scented flowers of the butterfly bush (Buddleia davidii) makes it an irreplaceable member of the landscape. These tough bushes grow quickly; attract pollinators, like butterflies; and resist disease like champs. They’re excellent choices for low maintenance landscapes, but even these low care plants may run into an occasional problem.
Brown spots on butterfly bush leaves are a common symptom in Buddleia when issues do occur. Buddleia leaf spot isn’t anything to worry about, though, as long as you figure out what’s causing it and manage it promptly.
Growers are often alarmed when leaf spots appear suddenly and spread across leaf surfaces. Buddleia leaves with spots can be caused by a few different problems, including fungal disease and sap-sucking pests. A butterfly bush with spotted leaves should be checked carefully from top to bottom before treatment, just to be sure you’ve fingered the right culprit.
Fungal leaf spots and downy mildew cause many widespread spots, ranging in color from yellow to tan and even black or brown. These spots may be circular or irregular, but they usually develop fruiting bodies shortly after they make their appearance. Fungal diseases need humid conditions to take hold.
Pests, like the four-lined plant bug and spider mites may cause brown spots where they’ve been feeding on the undersides of leaves. Four-lined plant bugs are elusive, but can be observed feeding on leaf tissues if you look carefully. These black bugs bear yellow-green stripes running from their fronts to their backs as adults, or appear red with small black markings as juveniles.
Spider mites are so tiny that you may only notice small moving dots and fine silk where damage has occurred. They typically cause a damage pattern known as stippling, where many small tan to brown dots appear on plant leaf surfaces. These spots will grow together as the colony expands.
If the leaf spots in question are few and aren’t spreading aggressively, treatment is not recommended, since many beneficial insects use butterfly bush as a food source. Simply pick off the damaged leaves and discard them away from the plant. The aggressive growth of Buddleia will quickly replace those missing leaves.
Fungal diseases like leaf spots and downy mildew are encouraged by high humidity, so opening up the canopy by thinning the inside and pruning the bush away from structures may help destroy the fungus. If it’s spreading rapidly, or pruning doesn’t seem to be helping, spraying both upper and lower leaf surfaces with neem oil every seven to 10 days will destroy fungal leaf diseases in no time.
Plant bugs can be hand-picked off of the plant and crushed or dropped into a bucket of soapy water if their numbers are large. Usually, this isn’t necessary, since these bugs appear for only a short period and rarely in large number. Spider mites, on the other hand, should be treated with neem oil or insecticidal soap weekly until new damage stops; they’re difficult to see, so you’ll have to rely on your plant’s health to know when these pests are gone for good.
In it's native jungle habitat, pothos ivy (Epipremnum aureum) -- also called golden pothos or devil's ivy -- is a vigorous climber. In a hanging planter, however, the vining growth tumbles over the edge creating a cascade of leaves. Though not commonly affected by disease, pothos isn't immune to problems. Small brown raised spots or larger patches on the leaves indicate a fungal problem. Advanced leaf spot can kill a pothos, but with early treatment, you can prevent the disease from taking a firm hold. Pothos grows in U.S. Department of Agriculture plant hardiness zones 10 through 12.
Pick off leaves affected by fungal leaf spot using your fingernails or a pair of small clippers.
Sanitize the clippers by wiping them clean with rubbing alcohol. Wash your hands with soap and water after working on an infected pothos plant.
Keep water and mist off the leaves so that they remain dry. When you water, soak the soil around the roots being careful not to splash any on the foliage. Move container plants growing in a humid environment to a dry area, and allow the soil to dry out slightly between waterings.
Relocate container-grown pothos plants demonstrating signs of fungal leaf spot to an isolated area away from other houseplants. Find a spot that has similar temperature and light to the original spot.
Set up a small fan near indoor pothos plants to keep the air moving and minimize the spread of the fungus that causes fungal leaf spot.
Thin out dense, overgrown pothos plants in the garden to improve air circulation. Clip the stems near the soil line.
Eulalia Palomo has been a professional writer since 2009. Prior to taking up writing full time she has worked as a landscape artist and organic gardener. Palomo holds a Bachelor of Arts in liberal studies from Boston University. She travels widely and has spent over six years living abroad.
Somebody please help - tree death messing up my whole plan!!
Help with landscaping the front of our house
Thanks for the link, Ken. This really makes me mad (especially as I am still recovering from the planting 40+ shrubs, grasses, and perennials over a 2 week period only a month ago!).
I checked out the link and I did everything correctly, but I knew this since I've been planting stuff for over 30 years. The only thing I didn't do is plant in native soil, which is crap (sand-clay) so I used a mixture of other soils along with the native stuff. Shoot.
So what do I do? Leave it alone and see what happens? Almost everything else I planted is doing well (although I still have my fingers crossed, and will do so over the winter).
BTW, no fertilizer on anything until next spring.
Pieris, like its rhododendron cousins, is subject to a number of fungal infections which cause the sort of leaf discoloration shown in the photographs. There are fungicides which can prevent it, but none, at least that I am aware of, are curative. Most growers just live with it as such infections are not a serious threat to the plant's overall health. Removing fallen leaves may be somewhat helpful in preventing re-infection next year. Chances are you did nothing wrong in planting, watering or soil preparation. Environmental conditions over which no gardener has any control such as humidity, temperature and rainfall do play a role. Leaf spotting may be very minor in some years and more noticeable in others.
An exception I would add to the above is the possibility of phytophthora ramorum, the pathogen responsible - in another form - for Sudden Oak Death as the cause of the spotting. Laboratory analysis is really the only way to differentiate p. ramorum from the many other infections which look very similar. It's highly unlikely that p. ramorum infected plants are still being circulated with the rigorous inspection and reporting systems in place, but it might be a good idea to contact your state agriculture department to see if there have been any incidences of infected plants showing up near you.
Alternaria Leaf Spot: Small, round reddish brown spots with white to gray centers form on the upper surface of the leaves. The lesions may encircle the stems and cause wilt. This disease is worse in warm, wet or very humid weather. Burpee Recommends: Avoid getting water on the foliage. Remove infected plant parts and do not work around wet plants. Provide plenty of air circulation. Contact your Cooperative Extension Service for fungicide recommendations.
Downy Mildew: This fungus causes whitish gray patches on the undersides and eventually both sides of the leaves. Burpee Recommends: Rotate crops with plants in a different family. Avoid overhead watering. Provide adequate air circulation, do not overcrowd plants. Do not work around plants when they are wet.
Root Rots: A number of pathogens cause root rots of seedlings as well as mature roots. Burpee Recommends: Pull up and discard infected plants. Make sure your soil has excellent drainage. Contact your Cooperative Extension Service for recommendations.
Tomato Ringspot Virus: Some butterfly bushes are susceptible to this virus disease which causes an overall decline in the health of the plant, and yellowish, wilting foliage. It is spread by nematodes through the plant roots. Burpee Recommends: Control for the disease by controlling nematodes. Remove and destroy infected plants.
Verticillium Wilt: First seen on leaves in late spring after fruit production has begun. Leaves turn brown along margins and between veins. Leaves will wilt and dry up as the disease progresses. Burpee Recommends: Remove infected plants. Do not plant in areas of infection.
Aphids: Greenish, red, black or peach colored sucking insects can spread disease as they feed on the undersides of leaves. They leave a sticky residue on foliage that attracts ants. Burpee Recommends: Introduce or attract natural predators into your garden such as lady beetles and wasps who feed on aphids. You can also wash them off with a strong spray, or use an insecticidal soap.
Caterpillars: Butterfly bushes attract butterflies, which begin their lives as caterpillars. Burpee Recommends: Do not destroy all caterpillars, but to avoid foliage damage hand pick or knock them off with a strong spray of water.
Nematodes: Microscopic worm-like pests that cause swellings (galls) to form on roots. Plants may wilt or appear stunted. Nematodes can spread Tomato Ringspot Virus. Burpee Recommends: Do not plant into infested soil. Grow resistant varieties. Try planting ‘Nema-Gone’ marigolds around your plants.
Slugs: These pests leave large holes in the foliage or eat leaves entirely. They leave a slime trail, feed at night and are mostly a problem in damp weather. Burpee Recommends: Hand pick, at night if possible. You can try attracting the slugs to traps either using cornmeal or beer. For a beer trap, dig a hole in the ground and place a large cup or bowl into the hole use something that has steep sides so that the slugs can’t crawl back out when they’re finished. Fill the bowl about ¾ of the way full with beer, and let it sit overnight. In the morning, the bowl should be full of drowned slugs that can be dumped out for the birds to eat. For a cornmeal trap, put a tablespoon or two of cornmeal in a jar and put it on its side near the plants. Slugs are attracted to the scent but they cannot digest it and it will kill them. You can also try placing a barrier around your plants of diatomaceous earth or even coffee grounds. They cannot crawl over these.
Spider mites: These tiny spider-like pests are about the size of a grain of pepper. They may be red, black, brown or yellow. They suck on the plant juices removing chlorophyll and injecting toxins which cause white dots on the foliage. There is often webbing visible on the plant. They cause the foliage to turn yellow and become dry and stippled. They multiply quickly and thrive in dry conditions. Burpee Recommends: Spider mites may be controlled with a forceful spray every other day. Try hot pepper wax or insecticidal soap. Check with your Cooperative Extension Service for miticide recommendations.
Do I need to prune my butterfly bush? If so, when? Yes, you should prune butterfly bushes to keep them rejuvenated, bushier and more floriferous. They bloom on new wood, so prune butterfly bush in the spring back to the new green growth.
Is butterfly bush native to the United States? No, it is native to China.
Will my butterfly bush attract pollinators? Yes, it will attract butterflies.
Is butterfly bush good for cut flowers? Yes, they make great cut flowers and are very fragrant.
How long does butterfly bush bloom? Butterfly bushes blooms from June to September.
Request a catalogBuy a gift card
Special offers, discounts, and new products.