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Brown Edges On Roses: How To Treat Brown Edges On Rose Leaves

Brown Edges On Roses: How To Treat Brown Edges On Rose Leaves


By Stan V. Griep
American Rose Society Consulting Master Rosarian – Rocky Mountain District

“My rose leaves are turning brown on edges. Why?” This is a commonly asked question. Brown edges on roses can be caused by fungal attacks, extreme heat conditions, insect attacks, or may actually be normal to the particular rosebush. Let’s take a look at each possibility in this article so you can find out why your rose leaf edges turned brown and how to treat brown edges on rose leaves.

Fungal Issues and Brown Edges on Roses

Fungal attacks can cause the edges of rose leaves to turn brown but, usually, the brown edges on roses are not the only sign of the attack. Most fungal attacks leave their mark on the overall leaf or leaves as well.

Black Spot will leave black spots on the leaves usually followed by a yellowing of the leaf once it has a firm hold on the leaf or leaves.

Anthracnose, Downy Mildew, Rust, and some rose viruses will also result in leaves going brown around the edges but also have other effects upon the leaves under attack.

The best method for how to treat brown edges on rose leaves due to fungus is to not let the fungi get going in the first place. Maintaining a good fungicide spraying program will go a long way to keeping them at bay. In this case, an ounce of prevention is truly worth more than a pound of cure! I begin spraying my rosebushes when the leaf buds first form in the spring and then follow-up sprayings at about three-week intervals throughout the growing season.

My personal preference is to use either Banner Maxx or Honor Guard for the first and last spraying of the season, all sprayings between those are with a product called Green Cure. The fungicides used have changed over the years as I see what works well and does the job with the least impact upon the environment.

Buying disease-resistant rose bushes does help, just remember they are “disease-resistant” not disease-free. Given some favorable conditions, fungi and other diseases will cause disease-resistant rosebushes some problems as well.

When Rose Leaf Edges Turns Brown from Extreme Heat

In times of extreme heat in the gardens and rose beds, the roses can have problems getting enough moisture to the far outer edges of rose leaves, as well as the outer edges of the petals on blooms, thus they get burned by the heat.

The only thing we can really do is to keep the rosebushes watered well and make sure they are well hydrated over strings of hot days. There are some sprays on the market that can be used to help try and hold some moisture throughout the leaf, and thus protecting the edges. Keeping the rosebushes well-watered is a must regardless of the use of the sprays.

When I have strings of extremely hot days in my rose beds, I like to go out in the early evenings and rinse down all the rosebushes with my watering wand. In the early evening, the temperature has started to decrease and there is not usually a problem with the water causing foliage burn due to the sun making the water droplets into little magnifying glasses.

Insect Problems Lead to Leaves Going Brown Around the Edges

As with the fungal attacks upon the rosebush foliage, insect attacks will usually show signs of the attack throughout the leaf structure, and the brown or dark-colored edges are just one of the signs of a problem.

Spraying the rosebushes well with a good insecticide at the earliest stages of having noticed a problem is very important. It just takes longer to get things back under control if they have gotten way out of hand. Take time to look over your rosebushes and other plants well at least once a week as a minimum.

Normal Browning of Rose Leaves

Some rosebushes have leaves that turn a dark reddish-brown at the edges once they have matured. This really makes for some great-looking foliage on those rosebushes and is not a problem of any kind.

The darkening edges are natural to the growth of the rosebush and may actually be something the rose breeder was trying to achieve. In my experience, the rosebushes that have this fine trait really look nice in the rose bed as it helps bring out the beauty of the overall bush when in full bloom.

Now that you know the common causes for rose leaves turning brown, you can choose the one that best fits the reason that answers your question of: “Why my rose leaves are turning brown on edges?”.


Growing Gardenias, Caring for Gardenias, Gardenia Diseases

Beloved for their intoxicating fragrance and attractive, waxy, creamy-white flowers contrasting beautifully with their shiny, leathery, dark green leaves, Gardenias are irresistible evergreen shrubs or trees. Native to the tropical and subtropical regions of Africa, southern Asia, Australasia and Oceania, Gardenias may be fussy and quite temperamental in their cultural needs.

If your Gardenia's leaves turn brown or display brown spots, this may be caused by any of these reasons:

  • Low humidity: Gardenias demand high humidity to thrive. Provide extra moisture with daily misting, set the plant on a tray of moist pebbles and/or use a humidifier. Extra humidity is important in keeping down spider mites that thrive under dry conditions.
  • Water splashed on the leaves when watering the plant. Drip-irrigation will keep water off the foliage and flowers and prevents leaf spots.
  • Poor soil drainage: Make sure your Gardenia soil is moist but well-drained.
  • Insufficient light: Although a Gardenia plant prefers full sun, some shade is appreciated during the warmer months of the year or its leaves may scorch and its buds may fall off if they get too much sunlight. In hot climates, Gardenias grow best with morning sun and afternoon shade. In cooler areas, they can tolerate full sun, especially if their roots are covered with organic mulch. Gardenias growing in containers need bright light or filtered shade with no direct sun. Gardenias grown indoors should receive at least 6-8 hours of direct sunlight through a sunny window.
  • Inadequate Ph: Gardenias prefer acidic soils with a pH between 5.0 and 6.0.
  • Pests and microbial threats: Powdery mildew, leafspot and sooty mold can cause your Gardenia leaves to brown and wilt. Similarly, aphids, scales and spider mites can attack gardenia leaves. Check your plant for pests underneath the leaves and on the stems. Spraying your gardenia with an antifungal agent (such as horticultural oil with baking soda and insecticidal soap) can reduce the risk of infection or infestation.


Why Are My Laurel Leaves Turning Brown?

Leaf spot, drought, frost damage and environmental conditions are some reasons laurel leaves turn brown. Laurel is affected by leaf spot, causing yellowing and browning of the leaf tissue and irregular blotches, lesions and spots. New plants are most susceptible to drought damage, while frost harms the plant at any stage of growth. Well-drained soil with a pH level over 6 and a sunny location are necessary for best development.

Treat leaf spot by raking up and removing dropped leaves to prevent the fungus from spreading. Mix 2 teaspoons of fungicide powder containing benomyl with 1 gallon of water, and apply evenly over the foliage every two weeks in the spring.

Water plants weekly during a drought. The soil should be saturated 12 to 18 inches deep. Mulch around the base of the plant to hold in moisture.

Laurel should only be planted in U.S. Department of Agriculture zones 4 through 9. If the plant is harmed by an unexpected cold snap, prune out dead or dying branches to reduce the possibility of attracting pests and diseases.

If mountain laurels are located in an area with clay soil, plant them in a raised bed to improve drainage. Plant near other trees to create a canopy of dappled shade.


Pesky Pests

Insect pests can wreck havoc on even the most lovingly cared-for rose bushes. Sap-sucking insects such as aphids and spider mites cause stippling and browning of the leaves. Chewing insects such as sawfly larvae and Japanese beetles strip away the tender, green tissue, skeletonizing the leaves or leaving only the brown lower leaf surface exposed. Cane beetles attack the canes, which blocks nutrients and water from reaching the leaves, causing them to turn brown, shrivel up and die. Luckily, it's fairly easy to tell if insects are infesting your rose bushes. If you see them, spray them with an insecticide. Choose one designed to eliminate insects that attack roses, and follow the application directions according to the size of your rose garden and the severity of the infestation.


Pests

A variety of pests are attracted to strawberry leaves. The stress caused by certain insects will make the leaves wilt and turn brown around the edges. Leaf rollers do exactly that -- they roll leaves together to feed on them. Feeding damage creates wilting and jagged holes in leaves. Mites suck the nutrients out of the leaves, creating discolouration.

  • A variety of pests are attracted to strawberry leaves.
  • The stress caused by certain insects will make the leaves wilt and turn brown around the edges.

Brown Leaves on Coffee Plant

Hi all,
I'm new to the Dave's Garden forums, but have been using the website for years. This is by far one of the best plant websites online. I purchased a young coffee plant at a local garden center late last spring. Over the summer it did very well in part shade, but it has since struggled greatly after being moved indoors to a bright, southern facing window to overwinter. Although there were four or five coffee plants, only one survives now. The upper leaves still look quite good as do the bottom ones, but the middle leaves begin bleaching-out around the edges, going from a dark green to light green to yellow then brown. The patches grow from the end toward the stem, becoming crunchy and brittle until the leaf is dropped. I have had this problem every time I have tried to grow coffee, yet many I've talked too insist it is very easy to grow. I suspect it could be low humidity (its current location is in a bathroom however) or overwatering. Any comments would be much appreciated. I have posed several pics. Thanks!

What are you using for soil? Is the soil usually still moist when you water? What have you done about fertilizing over the last several months - be specific? Is it situated so it gets direct sun where it's sited now? Has it ever been repotted (as opposed to potting up), and how tight are the roots?

@ tapla It is currently potted in an 8 in ceramic pot with miracle grow African violet potting soil (I read that coffee plants are acidophiles) I've only re-potted once from the original 4 in plastic pot they came in shortly after I got them. They've been re-potted in the African violet soil for about 9 months now. Over the summer they seemed fine. They got several hours of morning sun when they were outside, now they mostly get filtered afternoon sun. I try to let the pot dry out before watering, but I get the feeling its not completely dry most of the time when I re-water. I have grown several coffee plant before and this always seems to happen independent of supplier, soil, location etc., which leads me to believe its an environmental or cultural problem.

Oh, I agree it's a cultural issue - there's little question about that.

Fertilizer? What are you using? how often? what strength?

Are you giving just enough water to moisten the soil or are you watering generously so a significant fraction of the water you applied exits the drain? The interveinal chlorosis indicates some nutritional issues that could either be resultant of fertilizing habits OR something cultural that is preventing uptake. The necrotic spots on the leaves are likely from a high level of dissolved solids in the soil (solution) or over-watering.

Your pots DO have drain holes & are not self watering? and we needn't be concerned that the temperature is dropping below 55* where you have the plants?

During the winter I usually back way off the fertilizer, but typically I use miracle grow diluted to about 1 tablespoon per 1 1/2 to 2 gallons. I would say it has been at least three months or more since I've last fertilized. The soil usually isn't waterlogged, but I try to water thoroughly (until water drains out of the bottom) and then let the top 1 1/2 in. of soil dry out before rewatering. The pot has one almost thumb sized drain hole at the bottom with a good layer of small stones to aid draining. I havent misted it or given it much other attention. I've seen this before, so I'm trying to figure out the cycle lol

@tapla Thanks for all your help, I really appreciate it. I've since repotted it with fresh, Citrus/Cacti Soil so that it helps keep water from hanging around the roots too long. I've also lightly fertilized with Miracle Gro diluted to the recommended level for houseplants, and put it up near a room humidifier in a southeast facing window. I'm hoping all this helps it take off again

If you were only allowing the top 1/2" of soil to dry before watering, the probability is high enough to be a near certainty that over-watering has been an issue. If you were using a commercially prepared, peat-based soil, it should be noted that almost all are excessively water-retentive to the point where they should be almost dry at the bottom of the container before the next watering. Using wooden skewers until you get a feel for what is the most favorable interval between waterings is a good idea. Insert the skewer deep into the soil if it comes out dark/damp/dirty looking, withhold water.

Viewed as a group, most hobby growers have no idea how important soil choice is to the potential for their success as growers and, of all the things we have any significant control over, choice of the soils we use probably has more sway over what we get back in return for our efforts than any other consideration. Using an appropriate soil allows you to work WITH the plant sciences toward healthier and more attractive plants, while an inappropriate soil choice always finds us battling against the limitations imposed by the very foundation of our plantings.

You're on the right track if you chose the soil you're using now with the thought in mind that you'll be reducing water retention, but my experience shows that most soils labeled as being for cacti, succulents, other specific plants, don't carry the concept far enough because the packages aren't willing to let go of a high % of fine particles in their soils.

Let me suggest some reading that will hopefully leave you with a better understanding of how important soil choice is to your success as a grower. I have helped thousands of people become better growers, and I can say without being the least bit bashful about it, that an understanding of how soils and the water/air they retain represents the largest step forward you can make at one time.

If you haven't read the 'sticky thread' at the top of this forum page, I think you'll find it helpful.


Salt Build-Up in the Soil

Brown leaf tips can also indicate a buildup of salts from fertilizers over time or from softened water. Most potted plants do need a little fertilizer once in a while so they have all the nutrients they need to grow. But just like our own bodies and vitamins, remember that a little goes a long way and more is not necessarily better. Even when you're feeding your plants just the right amount, salts do tend to accumulate in the potting mix (not adding enough water to drain out the bottom makes it worse). That's one reason it's a good idea to repot with fresh soil every couple of years. Softened water can also turn the leaf tips brown, so consider using distilled or filtered water to keep your plants happy.