TREES and SHRUBS

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Question:

I’m on a tiny post-war lot near Neil Campbell Elementary School. I have one area with full sun along a wall that seems ideal for espalier apples. This is my third attempt in 4 years and I’m afraid to prune for fear of wrecking another tree.  I have not purchased whips. Previously I bought 2 and 3 year old dwarf trees in pots from local Winnipeg garden centres.   I’ve never seen whips for sale before. Perhaps this is a special order?  Glad I’ve found this association.

Answer:

Thank you for reaching out to the Manitoba Master Gardeners with your question.
You are writing that it is your third attempt in four years to espalier an apple tree and as I gather you assume it was your pruning that the first two trees did not survive.

A basic rule when pruning trees and shrubs is to never remove more than 25% of the canopy or branches as enough photosynthesizing leaves are needed to provide the tree with energy to build and sustain its root system and to put out new growth and eventually fruit. So when you train a young apple tree to its horizontal supports keep this in mind.  If you are not sure if a branch should be shortened or removed it is better to leave it as you can always go back and prune it in a second step when needed.

In early spring, end of March/beginning of April cut back the central leader to above 45cm/ 18″ of the lower branches, leave three good buds to form the new central leader and next level of horizontal branches.
If there are additional lateral branches growing from the main stem cut those back to three buds. ( I have read the recommendation to shorten the horizontal arms by about a third to a downward facing bud but did not do this because the horizontals did not seem very long and I did not want to compromise the tree by removing more of the branches). Keep doing the above steps until the tree has reached its last horizontal support.

Next is the summer pruning to keep the tree in its espalier form: I do this just once in early July because the tree I grow, a Norkent apple, does not put enough new growth out to warrant a second pruning six weeks before our average first frost date between September 16th and 22nd. If pruned later than six weeks before the average first frost date the new branches don’t have the time to harden off to survive our winter.
Cut back only new shoots on the horizontal branches and the stem that are more than 20cm/8” long. Cut those back to three leaves above the basal cluster of leaves.
It is important not to remove new growth that is less than 20cm/8” long as these short branches usually end in a fruiting bud or are fruiting spurs.

There may also be some long very vigorous and upright new growth on the horizontal branches; these can be cut off completely.

Once the tree has filled its space cut back the new growth of the central leader and horizontal branches.

When you train the branches to the horizontal you may have to do this in two steps to prevent them from breaking: first bend the branches to only a 45 degree angle to the main stem with the help of a bamboo stick tied to the wire support and then in a second step at the end of the growing season lower them to their horizontal support.

I add two links one with general information pertaining to our climate about growing apple trees from the University of Saskatchewan and the other one an article about espalier which may be of interest to you.

https://gardening.usask.ca/gardening-advice/gardenline-nested-pages/food-plant-pages/fruit/apples.php#Apples

How to Espalier an Apple Tree

Neither have I started my espalier tree from a whip but from a young tree for the same reason as you. The tree had a fairly flat crown and was slowly trained on to its support structure. It is a somewhat unusual way to start an espalier, which, as you correctly observe, is usually recommended to be done from a whip, but if you are not set on trying to create the perfectly espaliered apple tree it does still work.

I attach a few pictures to illustrate an example of the process and the end result. Image 1 shows the tree with just the first horizontal trained. That same summer the branches for the second and third horizontals were chosen and tied to the support structure. The following spring the leader and additional side branches were cut back as described and the training of the last horizontal was started. In the photo from this spring (Image 2) with the tree just leafing out you can see that the second and third horizontal don’t come off perfectly from the main stem, but once the leaves develop this becomes barely visible (image 3, the tree how it looks today with the summer pruning done about two weeks ago). When you start espaliering a dwarf tree which is preferable, especially if space is an issue, your first horizontals would be trained quite a bit lower than what you see in these photos.

If you would like to start training an espalier from a whip I recommend you contact your preferred garden centre soon to inquire if they take such orders and when it would be the best time to place it.

 

 

 

 

 

Question:
The small tree is now growing the 3rd set of leaves. It lost all it’s leaves in the spring. They are rolled together and a larvae or insect is inside in a net similar to a spider net . This year the big tree was effected in the spot close to the other tree. I sprayed twice within 2 weeks. I’m not sure if that helped or if the insects just left.

Answer:
From what is seen from the photographs, one tree appears to be a Basswood and the other a Manitoba Maple. Since the tree has not been seen in situ in person, it is difficult in diagnosing the problem. It is critical to identify both the tree species and the insect or disease affecting it before taking action to remedy the situation.
It is suggested the rolled leaves are the result of Leaf Rollers. Leaf Rollers are common in Manitoba. Archips purpurana attacks basswoods, birches, aspens and willows. Moth larvae form-feeding shelters by spinning silk webs around young leaves and rolling them together. Single leaves may also be rolled into tight cylinders. The larvae may skeletonize the leaves, leaving only the veins in tact, or consume the leaves whole. Severed leaf segments remain within the silk webbing and become bleached or brown.

When disturbed, the larvae become agitated and wiggle vigorously. They often fall to the ground or dangle from silk strands. The one inch long worm-like larvae is light green with a dark brown head. Leaf roller damage does not usually have an adverse effect on a tree’s vigour, as foliage loss is relatively low. But, aesthetic value is reduced by leaf disfigurement. To eliminate unsightly appearance, rolled leaves can be removed and heavily infested areas can be pruned.

Insecticides are often ineffective, because the larvae are protected within the rolled leaves and direct contact is inhibited. In future situations, biological insecticides such as Btk are effective when the larvae are exposed. As a guideline to treating any apparent infestation or disease, a diagnosis is critical before treating any problem. As with humans, treatment of trees without diagnosis is malpractice. It is important to know exactly what the problem is before applying any treatment.

A dormant oil application before bud break can effectively destroy over-wintered egg masses. Dormant oil is not recommended for maple trees.

 

 

 

 

 

Question:
We recently purchased a cottage in the Gimli area and believe this may be a type of apple tree, but am not sure. One of the branches has nice leaves and had some flowers however the other branches start to get leaves and then they appear to shrivel up right away before they reach full size. The first photo is the leaves looking like they may be ok to the 2nd photo showing how they turned brown and shrivelled up Can you please offer any advice of what I can do to save this tree

Answer:
There are two diseases that may be possibilities in your case. One is Fire Blight. Erwinia amylovora is very difficult to control. The disease develops rapidly in early spring during rainy, cool weather when temperatures around 15 degrees Celsius, and the tree is typically starting to bloom. Blossoms and young leafy twigs show the first signs — appearing wilted or shriveled and eventually turn brown to black. The tips of infected young twigs wilt and die, forming a shepherd’s crook as the disease moves down the branch. Dead leaves often remain attached to the branch. A milky-like sticky liquid carrying the bacteria can often be seen on the stems and branches.

Fire Blight is difficult to control. You can try this: remove all infection sources such as blighted twigs and cankers. Pruning should be made 12 to 18 inches below infected tissue. Disinfect all tools between cuts. Avoid high nitrogen fertilizers. Chemical control is difficult, requiring a daily regimen, often with unsuccessful results. Typical chemical recommendations for fire blight on apple trees is streptomycin or copper fungicide during bloom time. The prognosis is not good.

The second possibility is the fungus, Venturia inaequalis, known as apple scab. The disease causes serious leaf drop on susceptible crab apple trees. Period of rain and cool temperatures, as we had this spring provide conditions for apple scab to develop. Infected leaves on the ground from the previous year are the source of the fungal spores that can infect the carb apple the following spring. Spores from old leaves are carried on air currents to developing leaves. This primary infection produces olive-coloured spots on leaves.  As the fungus multiplies on the leaves, new spores are produced starting a secondary infection. Infected leaves become curled and yellowish with lesions, eventually turning brown. The disease causes premature leaf drop. It is too early for fruit, but infected fruit will have raised scab-like lesions and typically will fall to the ground.

Crab apple varieties vary greatly in their susceptibility to apple scab. Susceptible trees are often bare by August, making it difficult for the tree to store energy for future growth. A weak tree will find it difficult to overcome environmental stresses. Trees with apple scab often survive and will re-leaf the following spring. It can occur to a tree every year. If it is apple scab, you can choose to do nothing other than disposing of all dropped leaves. Or, you could apply a fungicide as a preventative treatment with a spray program that begins at the first sign of leaf emergence in the spring. But, you will need to determine first whether this tree does, in fact, have Venturai inaequalis.

There are steps to follow in the spring to help to protect the tree from Venturai inaequalis: Prune the trees in early spring (late March) to ensure good air circulation. It does not look like your tree has an issue with air circulation. Good circulation will ensure that the leaves do not stay wet after rain or dew. It does not look like this tree is being shaded or crowded by other trees, but if it is, try to give it as much space as possible. All crab apple trees need good air circulation and access to sunlight. Make sure sprinklers do not wet the bark or leaves of the crab apple tree. This will help to deter the disease. Sanitation is key. Rake up and dispose of leaves that have dropped around the tree. If trees in the neighbourhood have the disease, spores can blow in from elsewhere, but ensure you are doing what you can to keep the area clean.

You could choose to remove this tree and in its place plant a crab apple that is a resistant variety to apple scab. A third possibility would be Cedar-apple rust, but there would have to be a cedar tree growing in the vicinity.

If these suggestions do not appear to be consistent with what you are seeing, it will be necessary to have someone look at a branch from the tree for analysis. It would be recommended doing that regardless, as it is the only way to identify definitively the nature of the problem with your crab apple tree.

Question:
I have a lovely large many branched Amur Maple in my back yard. One large branch has developed a crack coming from the Y joint almost all the way to the base. We are thinking of cutting it off at the joint and hoping the tree will heal itself. Any advise would be welcomed.

Answer:
It is always very sad when we have a mature tree, that we enjoy in our yards, is showing signs of aging. This is a severe crack and the recommendation would be to call in a qualified arborist to come on site and access the issue. If the branch can be removed they would do so properly.


Question:
I visited Colleen Zacharias’s garden on a tour, and she said she uses Gaia Green fertilizer. I bought some but I would like to ask her to recommend how and when to use it. Maybe she could talk about it in the context of fertilization in general.

Answer:
Hydrangeas are heavy feeders and are also moisture-loving plants. To feed my hydrangeas, I add a 2- inch layer of compost every spring around each shrub, taking care to not place the compost next to any of the stem growth. In mid-summer, to help conserve moisture, I add a 2-inch layer of shredded leaves to the soil surface layer around my shrubs, which, through the decomposition process over time, also contributes nutrition. When my hydrangeas begin blooming, I add a small amount of Gaia Green Power Bloom which is an organic high phosphate fertilizer “specifically formulated to support prolific flowering”. (I want to believe this but at the same time, I would not use Gaia Green in place of compost).

Gaia Green Power Bloom includes the following:
Bone meal, mineralized phosphate, fishbone meal, rock phosphate, mined potassium sulphate, glacial rock dust, insect frass, feather meal, basalt rock dust, kelp meal, humic acid, gypsum, greensand, blood meal. Some information about Gaia Green that I included in my column some years ago: Glacial rock dust is a natural mineral product that aids in improving soil structure. It is a good source of calcium, iron, magnesium and potassium. Fish bone meal is high in phosphorus and promotes rooting and flower development. Bat guano is also a good source of natural phosphorus. It is used in annual containers to promote bloom production and enhances yield and flavour in vegetables.

The directions say to broadcast and incorporate up to 1.4 kg per 10 square feet. I don’t use nearly this amount.
One thing about Gaia Green is that it is very fine — a dustlike texture. It is important to apply it on a calm day, early in the morning, and to water deeply following application.

Years ago I talked to Michael Dean, the founder of Gaia Green, for my column:
Michael Dean is the creator of Gaia Green Organic Fertilizers. Started in 1990 in Grand Forks, B.C., Gaia Green is sold across Canada. Dean is a passionate advocate for shifting the emphasis from fertilizing plants to one of feeding and remineralizing the soil.

“There are over 75,000 different species of beneficial bacteria,” Dean says, “and 25,000 to 30,000 species of beneficial fungi that live naturally in symbiosis in our soils and these organisms convert nutrients.” Each of these beneficial organisms have different roles in breaking down nutrients. Some, says Dean, digest minerals such as manganese, boron and selenium, and when they are provided with their food source, their population explodes.
Dean includes a wide variety of ingredients in his blended products to activate as many of these species of bacteria and fungi as possible and convert these natural nutrients into plant available forms. By activating the soil food web, the resulting healthy soil ecosystem, says Dean, has a profound effect on plant vitality, allowing it to function at its highest potential. “Healthy plants are more naturally resistant to disease and pest infestation and have greater drought tolerance,” he adds.

Dean eschews the conventional methodology that says chemical fertilizers consisting mainly of nitrogen, phosphorus and potassium (NPK) are the best approach. “Chemical fertilizers are in ionic form, and they are totally soluble. A third of it washes away into the ground water, creating environmental pollutants, and another third volatizes into the air in hot weather, actually evaporating.”

Question:
I have hardy roses I bought from the garden center this summer. Several of them are 24 inches high and a climbing rose that has grown to reach the roof of my pergola. So how do I prune and protect the 24-inches high one and the climbing one this winter? Here are the names:
Shrub rose – Therese Bugnet
Hardy Rose – Grootendorst pink
Hardy rose- Alexander Mackenzie
Climbing Rose – John Cabot

Answer:
The short ones, providing that they are either the Parkland (from Morden) or the Explorer (from Ottawa) series, or even the Artist Series (Bill Reid, Emily Carr, etc. or the 49th Parallel Series (Aurora Borealis, Chinook Sunrise, etc.), the recommendation is that you don’t need to cut them down, or do anything at all to them, they are hardy in our Zone 3 climate. If the climbing one is William Baffin (an Explorer), you wouldn’t need to cut it back either, other than to tidy it up. My William Baffin got chewed up by rabbits over the winter, but it came back gangbuster this spring, and is now around 7 feet tall. I just leave it alone and let it do its own thing. If, however, it is not one of the above series, then I would be more careful with winterizing it.

Therese Bugnet is a hardy rose bred here in Canada, Alexander Mackenzie is of the Explorer series, as is John Cabot while the Grootendorst roses are rugosa roses, and are very hardy as well.

Therefore, I would say don’t bother cutting these roses back, other than John Cabot, which grows fairly tall, and I would suspect that is the one that was labeled as a climbing rose. If it is taller than 4 feet right now, you could cut it back to 2 feet, but not essential. Do not worry about winter either. You purchased a nice selection of hardy roses. They should do very well for you next summer.


Question:
I had the question about Jostaberry bushes on the CBC radio this morning. The bushes are about 3 years old with no fruit produced yet. They are running wild. See attached photo. What fall treatment do they need? Pruning? I live just outside of Winnipeg.

Answer:
I was very interested in your question and did research your Jostaberry shrub. It is of the Ribes family which gooseberries and currants belong. Jostaberry is a cross between black currants and gooseberries. They are very disease resistant and self fertile (meaning one needs only one plant to bear fruit) but have slow fruit set. Birds love the fruit and it is recommended that the shrub be covered with a row cover to protect the produce. Pruning would be done in late winter or early spring but can also be done in autumn once the leaves fall. Unless the branches are diseased or damaged do not shorten or cut back the canes (branches), as the spurs which produce the fruit, would be unknowingly removed. Most of the fruit for Jostaberries are born on 2 and 3 year old canes. The goal to pruning Jostaberry is to keep 3 or 4 strong new canes per year, and to remove an equal number of old canes per year. In this system, mature plants have 9 to 12 canes after pruning; 3 to 4 each of 1 – 2 and 3 year old wood. Remove all wood that is 4 years old or older. When removing the canes cut them as close to the ground as possible. And remove any canes that are drooping and close to the ground.

Question:
I noticed a while back that the leaves on one of my lilac bushes were all cupped up. Yesterday I noticed that another bush also has some leaves that are cupping. I did give them some miracle grow in the spring, would this do it? Or do I have some kind of disease in them. I have several bushes in my yard and am scared I will loose them all?

Answer:
The cause of your lilac leaves cupping in this manner would be caused by a herbicide being sprayed in close proximity to your shrubs. Unless the miracle grow was a very strong concentration, more so than the directions given on the package, it too can affect the lilac. But the general consensus would be a herbicide ie. Killex or something similar. If it was applied on a windy day the spray can easily be blown to affect a wider area.

Question: I have 3 Winnipeg Parks Roses amongst my plantings in the front of the house in an eastern exposure. The plants are 2 older (+6 years & 1 2nd year). The blooms are many, beautifully formed, no problem. In the last 1-1/2 weeks, I have noticed leaves dying, and this morning, many on each plant are dead. I have dusted with Rose dust- not for any reason other than I thought it may be bugs, but do not see any. I would usually fertilize this week with Miracle grow Rose food. Can you suggest what procedures I should follow to identify the problem & get these back on track. I used Larter’s Rose & Flower Dust which supposedly is an Insecticide & Fungicide. As I said this were looking great until about 1-1/2 weeks ago… then ??

Answer:
The leaves looking like this is caused by rose sawfly. It is too late for this year but leaves should grow back and the suggestion is to hand pick off the larva early next spring or blasting them off with a water jet. Insecticidal soap also kills them safely. They only produce one lot of larva per season so there shouldn’t be any new damage.

Question:
I would appreciate if someone could advise me of a small rose bush perennial that would get morning sun (east) against our concrete foundation. I have had no luck previously with black spots, aphids, etc. killing my rose bushes. I see there is a Parkland and Canadian Explorer series that are improved to deal with these problems. I live in a private condo home and residents drive by this area of my home on entering our condo village. I would like a small one due to winds and condo restrictions of 36-40 inches and other plantings restricting width so 24-36 H & the same wide is what I am searching for.
Also I have had ant problems for which I have used Ant Out recommended by a St Mary’s garden shop and also homemade cornstarch and icing sugar which never got to the queen ant. Any suggestions would be appreciated.

Answer:
Roses need some sun to flower well, they will manage with less, just flower less. Overall roses are difficult to grow well here, they may just survive and not really do a lot, also foundations often don’t get much rain. It is likely alkali near your foundation and roses don’t really mind that. It is worth a try but this is not the best position for a rose. Roses do best in an open full sun position in a bed that only has roses in it, they don’t like competition, heavy clay is fine for them as they like to be fed well and stay a bit moist. Your conditions are not ideal but may be adequate.
There are as you suggest the Parkland and Canadian Explorer series of roses. Most of the Morden roses such as Morden Blush, Morden Ruby, Morden Fireglow are small as is Winnipeg Parks. The Canadian Explorer series tend to be larger but Henry Hudson and Simon Fraser are small. There is a new series of hardy for zone 3 roses called the Artist Series, Oscar Peterson, Campfire, Emily Carr, Bill Reid and Felix Leclerc. You haven’t mentioned what colour you want. Many roses are partially frozen in our winters but if these are bought on their own roots (not grafts) then even if they are frozen down to the ground the same rose will come back. It is often hard to grow a rose to its full potential so some of the bigger ones may never get to that size.
There is quite a variety of these hardy roses in the box stores garden centres in Winnipeg and without naming names some for as little as $10 each. The recommendation is to go on the internet and decide which colour and style you like then make a list and go around looking for it.
Aphids should be washed off with a hose jet and will likely be eaten by the new aggressive ladybugs. When choosing a rose look for disease resistance then you will have less trouble with black spot. Put some bone meal to encourage root development into the hole you dig and water regularly in the first year or two to help the rose establish. After winter when your rose has leafed out prune out the dead wood but be patient as some of the apparently dead branches will recover. It is unusual to have a problem with size as it is hard for even hardy roses to survive in our climate but if a rose grows too big then you can always prune it.
If the standard ant bait hasn’t worked for you , you could try Ant Nematodes which are little worms that infect and kill ant larvae. It is important that you get them before the use by date as fresh as possible and buying on-line seems to be cheaper and more available than in the local garden centres many of whom haven’t heard of this biological control.

Question:
For the last couple of years my rose bush, a Chicago Peace, has grown very well – tall, shiny green leaves – but it has not produced any buds or roses. I have fertilized it first thing in the spring ( with a rose fertilizer) and then watered it during the summer. It gets full sun all day.
I would appreciate any suggestions you could give me so that I can have the best chance of having it bloom next season.

Answer:
I presume you live in Manitoba and so in our climate it is often very difficult to get a Hybrid Tea Rose to survive the winter. Most Hybrid Tea Roses are grafted on a hardy root-stock (unless they are bought as specifically grown on own roots) . Often the freezing of winter will kill the graft but not the hardier root-stock which will then often grow vigorously next spring but unfortunately is unlikely to flower and if it does it will not be the beautiful Chicago Peace. In general you are doing all you can to encourage flowers most importantly growing in full sun, fertilizing and watering appropriately so I am sure your bush is in good condition but I suspect it is no longer Chicago Peace. Hardy roses for our climate are lovely but not as gorgeous as the big Hybrid Teas. Some winters a Hybrid Tea may over-winter very well depending on the winter experienced. One can tell the difference between the rootstock and the grafted rose by the number of leaflets on each compound leaf. There should be 5 or less on the Hybrid tea and 7 or more on the root-stock.

Question:

Ordinarily, my bushes shed the leaves in fall/winter. This last fall / winter (2017-18), they just turned brown and remain on the bushes and trees. Odd?

Answer:

The reason is that we had quick early cold winter temperatures and up until that time it was fairly mild. Normally, there is a slow degradation of temperatures, and trees adjust to this and prepare themselves for winter dropping their leaves so as not to lose too much moisture through them. When trees are preparing for winter the connection between the leaf stems and the branch, the abscission layer, produce an enzyme that facilitates the falling of the leaves. With our sudden cold temperatures this did not occur and hence your trees and bushes still have their dried brown leaves on them. Come spring they should be ‘pushed’ off the twigs when the new leaves begin growing.