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Browned Leaves On Mountain Laurel

Leaf-tip browning such as you see can be a result of a couple of problems and without a full-shrub examination it's hard to say which one is causing what you see. But we'll list the possibilities here so that you can do a bit more thinking about what might be the culprit in this case. Note that sometimes what we see in plants has two or three causes and we're seeing the results of more than one issue.
1) Drying or too shallow watering. When plants dry out between watering their leaf tips can brown like this. Be sure that this plant is being watered deeply every four to seven days - do NOT hand water as this is never deep enough. Use a sprinkler or soaker hose, or make sure irrigation systems are going on for more than 45 minutes to deeply soak the ground. Buy a rain gauge to accurately measure rainfall - most established plants are fine if they get one inch of water a week as measured in a gauge, not a tuna can etc. Try to deliver that much if Mother Nature doesn't manage it.
(Note: an inch of mulch or compost around a plant from just beyond the stem to a foot outside the dripline can keep the soil more evenly moist.)
2) Leaf fungus. Although this photo is a bit out of focus so it's hard to see for sure, we can see that there are some spots as well as the browning of the tips. This is usually a fungal issue and is often made worse by splashing the leaves with water. Be sure that this plant isn't getting hit with frequent water from hoses, lawn irrigation etc. If you suspect a fungal problem you can go to your garden center and ask for a fungicide labeled for leaf-spot on mountain laurel.
3. Fertilizer burn? If this plant was fertilized with a synthetic fertilizer shortly before you started to see symptoms, or if a nearby lawn or other plant was fertilized, this might be part of the problem. Too strong fertilizer causes edges and ends of leaves to brown. Always use fertilizer at rates recommended and never apply it to a thirsty plant.
4. Sunburn. Is this plant suddenly in more sun then it was before? Mountain laurel like to grow in places where they get some sunlight but are shaded from hot noon-day and afternoon sun. If this plant is getting hot sun all day or at the hottest part of the day, this could be part of the problem.

By | 2017-09-11T15:49:32-07:00 December 4th, 2015|Shrubs|0 Comments
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Butterfly Bush Or Summer Lilac

We believe this is a butterfly bush or summer lilac. They are butterfly magnets, however, it is not a native shrub and can be invasive as it self seeds regularly. In cold climates it can sometimes be an unreliable shrub as it may suffer winter damage and not return consistently.

Buddleias are vigorous growers that remain evergreen in winters with minimum temperatures of 20 degrees. Where winters are more severe they can be deciduous, merely dropping leaves, or herbaceous, freezing completely back to the ground. Leaving branches on until spring and mulching over winter are good practices for those in the coldest areas of zone 5. While flower colors are often referred to as blue, there are no true blue (or red) flowers in the Buddleia genus. Their colors range from very dark purple to pink to pure white. Some hybrids have orange and gold flowers. A 2 3/4 inch pot placed in the ground in early spring will grow to 3 or 4 feet in one year, and as much as 8-10 feet the following year. Butterfly bush care is easy. Water the shrub slowly and deeply during prolonged dry spells so that the soil absorbs the water deep into the root zone. The plants don’t typically need fertilization. Fertilize with a 2-inch layer of compost over the root zone or scratch in some general purpose fertilizer if you need to enrich the soil. Cover the root zone with a 2- to 4-inch layer of mulch. This is particularly important in cold climates where the roots need winter protection. The most labor-intensive part of caring for butterfly bushes is deadheading. In spring and summer, remove the spent flower clusters promptly. Seed pods develop when the flower clusters are left on the plant. When the pods mature and release their seeds, weedy young plants emerge. The seedlings should be removed as soon as possible. Young shrubs that are cut off at ground level may re-emerge, so remove the roots along with the top growth. Don’t be tempted to transplant the seedlings into other parts of the garden. Butterfly bushes are usually hybrids, and the offspring probably won’t be as attractive as the parent plant.

By | 2015-12-03T11:00:53-08:00 December 3rd, 2015|Shrubs|0 Comments
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Rhody Curling Leaves

Many Rhododendrons in the landscape look like this at this time of year in the Northeast. It is a sign of stress, and could be root rot, other root or stem damage from the winter, a combination of sunburn and wind burn, or a combo of all of these. With plants sometimes what we see isn't the result of just one thing but several combined.

1. Without culturing in a lab we can't know if it's phytophthora or not. That will be a time-will-tell kind of thing.

2. Look at the bottom of the plant - examine the stems carefully, especially from ground level to about 8" up. Plants that have been in snow are sometimes girdled by mice or voles eating the bark all the way around the plant. Once the bark is eaten, water is no longer carried up the stems to reach the leaves, so they curl.

3. Are these plants on a sunnier or windier side of the house? If so, this cold be sun or wind burn. Sunburn is especially hard on Rhodys when there has been a snow cover, since the sun reflects off of the snow and draws moisture out of the leaves. In such situations when the ground is frozen the plant can't replace the moisture that the sun/wind has drawn out and the leaves curl.

4. Are these a different variety of Rhododendron from your others. Different hybrids/species/cultivars are more or less sensitive to winter burns and stresses. In many landscapes you can see plants right next to each other and one variety is yellow and curled while another is healthy looking and green. The interesting thing is that in two months both plants look fine - the "damage" done to the curled one goes away as the temperatures warm.

At this point, other than considering the above, you should wait and see if these plants do indeed recover later in May. Provided that they don't have girdled stems (no recovery from that) you could apply a light application of an organic fertilizer and an inch of compost or composted manure all around the plant under the dripline and then wait to see if there is recovery. If they still look bad in mid-to-late-May you'll know they are gone. If water/drainage is an issue there don't plant Rhododendrons again - consider Winterberry Holly, red-twig dogwood or other moisture-tolerant plants.

By | 2015-12-02T07:07:52-08:00 December 2nd, 2015|Shrubs|0 Comments
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Scale And Winter Damage

Your bumpy stems and the brown leaves are due to two different problems. The bumpy stems are most likely scale although we'd need to see the plant "up close and personal" to be absolutely sure. Not only does scale cause brown dots and scars, but it also causes the grey-black look that we see on the stems here. That is sooty mold, which forms on the plant juices that sucking insects such as scale excrete. The mold isn't a problem, just a symptom that a sucking insect is at work. Look under the leaves that are above these stems - are there either small tan dots or white cottony things on the underside of the leaves? If so, that confirms that it's scale. Spray the plant with Horticultural Oil from your local garden center, applying it at least three times this season and coating the stems and underside of the leaves as well.

Cherry laurel is known for getting winter scorched leaves. Winter damage is caused by cold winds and/or sunburn from the sun reflecting off of the snow. The plants that most frequently show winter damage are the broadleaf evergreens such as Cherry Laurel, Rhododendrons, Holly, Camellias etc.

Because these plants have leaves that are scorched, the areas on the foliage that had some leaf spot damage from last summer are more evident. You'll see dark spots, or white spots where the leaf tissue actually died last summer or fall and now is turning tan or white. On some plants, such as cherry laurel, such dead leaf tissue often drops out and leave holes.

At this point there isn't anything that you need to do - the plant will drop this scorched foliage this spring and will put on new growth. To help prevent leaf spot in the spring and summer, make sure that the plants aren't getting hit with water from a sprinkler on a frequent basis, as this is a prescription for leaf-spot fungi. To help protect broadleaf evergreens in advance of winter you can use an anti-desiccant product in October, although in a really cold or snowy winter plants will still show some winter damage.

By | 2017-09-11T15:49:32-07:00 December 2nd, 2015|Shrubs|0 Comments
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Holly Shrub

This appears to be Holly, a shrub who's pointy leaves and structural shape can be attractive all year long. There are many varieties of this plant. The best location for planting holly bushes is in well-drained but not dry, slightly acidic soil in full sun. Most holly varieties are very tolerant of less than ideal locations and will grow well in part shade or dry or swampy soil. If you are growing a traditional holly bush for its bright berries, you need to keep in mind that most holly varieties have male and female plants and that only the female holly shrub produces berries. This means that in the location where you would like to plant a holly bush with berries, you will need to plant a female variety and you will also need to make sure that a male variety is planted nearby. There are modern holly varieties that do not need a male plant in order to produce holly berries. Definitely research before purchasing in order to find the variety that will work best for you. Special note* - Holly berries are poisonous to pets and humans.

The care of holly bushes after they are established is easy. Fertilize your holly bushes once a year with a balanced fertilizer. They do not need to be watered in normal conditions, but if your area is experiencing a drought, you should give your holly bushes at least 2 inches of water per week. When growing a holly bush, it also helps to mulch around the base of the holly shrub to help retain water in the summer and to even out the soil temperature in the winter.
Proper care for holly shrubs also calls for regular pruning. Pruning your holly bushes will ensure that they keep a nice compact form rather than becoming leggy and scraggly. If you find that your holly shrubs are being damaged in the winter by snow and wind, you can wrap the holly shrubs in burlap to protect them from the weather.

The initial care of holly bushes after they are planted is much like other trees and shrubs. Make sure that your newly planted holly bush is watered daily for the first week, twice a week for a month after that and, if planting in spring, once a week for the remained of summer.
Growing Holly Bushes

By | 2017-09-11T15:49:32-07:00 November 30th, 2015|Shrubs|0 Comments
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Two Possibilites But Different Pruning

If you could send a close-up photo of some of the foliage that's in focus it will be easier for us to identify this for you. From this distance there are two possibilities: the first is one of the spring-flowering spireas such as 'Snow Mound' and the second is a green-leaf barberry. If it has thorns, it's the barberry. If it blooms with white flowers in the spring it's a spirea. The pruning method depends on your goal. In general, it's best to prune plants for appearance NOT to control size. Unfortunately in the location where you have these shrubs this is hard to do in that you'll undoubtedly want to keep these plants from covering the windows. But both the spirea and the barberry are genetically programed to get at least 5 feet tall which presents a problem in that you'll be fighting the growth of these plants FOREVER. There will be a time, probably soon, when you'll have to admit that it's impossible to keep them small.

The other problem is that in order to keep them smaller you'll most likely have to shear them into a more formal hedge, instead of the more loose, informal look you have now. If you shear a spirea it removes the very characteristic that makes it attractive in the first place: the loose, flower-filled branches. Yes, you can cut it back after it flowers in the spring but you change the shape of the plant and it won't be as attractive in years to come. Likewise for the barberry.

In general, pruning for appearance involves first removing any deadwood, next cutting out (with pruners not shearing tools) crossed branches and anything that's wildly out of shape, and finally a snip here an there if needed but no wholesale cutting of the stems.

By | 2015-11-13T20:37:44-08:00 November 29th, 2015|Shrubs|0 Comments
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Leaf Damage On Annabelle Hydrangea

In this photo it looks like the damage is mostly on the bottom leaves near the ground, is that true? If so, that argues for something different that's going on in that area, such as the plant getting hit with a sprinkler that's watering a nearby lawn, for example. But whether the damage is seen just near the ground, or over the entire plant, there are several possible causes and you can think about what's most likely for your plant. (After the list we've also given you a recommended course of action even if you can't figure out what has caused this damage.)
1. Look under the leaves to see if there are small, green larvae (they look like worms) eating the tissue under the leaves. There are green "fruit worms" that sometimes eat the underside of hydrangea leaves, which causes the top tissues to brown and die. If you see any green larvae either pick them off and smash them, or spray the underside of the foliage with a product containing spinosad, an organic treatment that kills a wide range of larvae when eaten.
2. Fungus: the most common cause of leaf-spot on plants is a wide range of fungi. This is especially likely if parts of this plant are getting hit with water on a frequent basis, either by hand watering with a hose or a sprinkler system. Picking off the worst of the leaves and watering deeply less often (once a week) in the AM so that foliage has a chance to dry usually solves the problem. The good news is that leaf-spot fungus is usually just a cosmetic issue and doesn't kill plants.
3. Contact damage. This type of damage happens if foliage gets hit with something that kills the leaf tissues when it lands. Hot water from a sun-heated hose, liquid fertilizer mixed too strongly, cleaning products used to wash decks or windows, herbicides or drift from other garden products can all damage foliage. If this was the cause the damage won't continue unless what caused the problem also continues.

No matter which of these has caused your situation, picking off the worst looking leaves will help you to determine if the problem is still going on and will improve the look of the plant. If you suspect a fungal leaf spot you can use one of the organic fungicides such as Serenade, Actinovate or Sulfur, but that won't cure tissues that are already infected, it will only help to protect any undamaged leaves.

Know that most insects and diseases are very host-specific, so you don't have to worry that this is something that will "spread to everything else in the yard", which is understandably a common concern but not likely to happen.

By | 2015-11-29T04:15:22-08:00 November 29th, 2015|Shrubs|0 Comments
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Dying Thuga

These appear to be arborvitaes although the photo is so dark it's hard to be completely sure. These also look like plants that were recently put into the ground, yes? There can be several reasons plants get brown and die, and from a photo alone it's impossible to tell which reason has caused your plants to do this, but here are a few things that come to mind immediately:
1. These look like they were planted above ground level. It almost looks like a small berm was raised in order to give these plants a few more inches in height from the get-go, and this actually makes the plants roots dry out faster. The most common cause of a plant browning like this is too little water during the first and second year after planting, and raising up a mound to plant in or on doesn't help.
2. If these plants weren't watered deeply (using a soaker hose or sprinkler once a week for about two hours) the cause was probably drying out. Hand watering is never enough, especially when the ground slopes away from the plants as it appears to here. Automatic sprinkler systems that only come on for 15 or 20 minutes are also not enough as they only water the top three inches of the soil.
3. Was the burlap removed completely from the root balls if these were balled-and-burlaped plants? Burlap left on the rootball contribute to root-drying and early death of plants. Always take all burlap, rope, and wire cages off.
4. Fertilizer burn can also look like a plant has dried out. If the plants were given a synthetic fertilizer at too high a concentration, that would contribute to the death of plants.

There are so many plants here and they are so close together that even if you removed the dead ones, and pruned out dry branches from the others, the remaining plants might make it and become a good screen. But you'll need to add more soil so that they aren't on such a narrow ridge, mulch with some composted manure topped by bark mulch to hold water in the soil, and water them deeply once a week if it doesn't rain. Deep soaking less often is always better than a little every day.

By | 2015-11-28T03:07:36-08:00 November 28th, 2015|Shrubs|0 Comments
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Dying Burning Bush

We're assuming you're worried about the die back on the burning bush but not the shrub as a pest, yes? (This shrub is classified as a pest because it self-seeds and chokes out native plants. It is now illegal to sell in Massachusetts for this reason.) So we'll address the die back here:
While it is impossible to tell from a photograph what has caused a normally hardy plant to have die back as we see in this picture, some of the possibilities are as follows.
1. Too dry. This seems unlikely for your plant as the plants that are on the ground are still green, but it's something that might be a part of the problem.
2. Physical contact with something that killed the leaves such as hot water from a sun-heated hose, drift from herbicide sprayed on other areas, cleaning products such as deck or house washing, liquid fertilizer that's too strong and sprayed on leaves, other garden products that made the plant sensitive to sunburn.
3. Physical injury such as damage from a string trimmer that cut the bark.
4. Borer that got into the main stem - check for holes.
5. Vascular disease - root rot fungi, bacteria etc. This plant isn't prone to such diseases but it is a possibility.

Sometimes a combination of one or more of these will be what does a plant in. If the plant is mostly dead, take it out and use this as an opportunity to plant something more interesting than a burning bush. The Blue Shadow Fothergilla, for example, has white flowers in early spring, bluish leaves all summer and fantastic fall color!

By | 2015-11-27T22:54:35-08:00 November 27th, 2015|Shrubs|0 Comments
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Hydrangea Problem

Hydrangeas do best in partial shade and may burn if receiving high heat or light intensity, so you were right to move it. There are, however, many more adjustments you'll have to make to keep your hydrangea healthy. 1) It needs a bigger container. This is probably not the source of your problem, but if you want the plant to live more than on year it will need a larger container with a greater soil volume. I grow hydrangeas for clients in containers as large as 24" x 24". Your plant doesn't need that yet, but it will need a bigger container next year. 2) Hydrangeas need consistent soil moisture but their roots don't want to be always wet. You used the word topsoil. If your plant is really planted in topsoil, this is a problem. Professionals don't generally use topsoil in containers. it stays too wet too long and can lead to root rot. Promix is a lighter weight potting medium that may contain a little soil but is primarily composed of perlite, vermiculite, sphagnum moss, and humus. If your plant is truly planted in topsoil (not promix) you should repot it before winter. 3) How much water are you giving it each time you water? To encourage healthy root growth throughout the pot you need to water thoroughly each time. That means water until water runs out the bottom of your pot. You will want to water when the top half inch of potting mix is dry. Depending on the temperature and rainfall this might be every day, every other day, or twice a week. There is no set schedule...you need to feel it. 4) If you don't already know, you should try to find out what kind of hydrangea you have. We can't tell you this from the photo, but it looks like you may have the kind of hdrangea that is sold as a short-term gift plant around mother's day. The original seller may not know the species or variety but it's worth asking. If this is what we call a florist's hydrangea it may not be winter hardy in this area and won't come back next year.

By | 2017-09-11T15:49:33-07:00 November 27th, 2015|Shrubs|0 Comments
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