Tar spot on maple trees

In many cases, diagnosing plant problems requires an in-person look at the plant in question. Too many disorders look similar when all you have is a photo to go by.

Earlier this week someone sent me a photo asking about spots on a valuable tree they have in their front lawn. That was an easy one. I took one quick look at the photo and knew right away what it was. Their maple tree was infected with a fungal disease called “tar spot”. It’s quite easy to identify because in this case the name is very descriptive, the leaves really do look like they’re covered with spots of tar.

Tell-tale symptoms of tar spot.

Even though it looks pretty bad, tar spot is relatively harmless even in a heavily infected  situation. There’s no good way of preventing the disease. Some years are worse than others for tar spot and some varieties seem to be disposed to having more dramatic symptoms than others.

The spores from the disease over winters in fallen leaves so you wound think that raking them up and disposing of them would help the situation. Unfortunately the fungal spores can travel for miles in the air and can land on your tree and take hold.

When a tree has a severe case of tar spot, it can lose many of its leaves causing the tree raking season tobegin earlier than normal.

One bright spot is: since tar spot is species specific, it will not spread to other types of trees such as oaks.

Bob

Striped cucumber beetles causing problems

A couple of gardeners I know asked me why their cucumbers didn’t come up this year. Others have mentioned that their beans didn’t come up either. Was there something wrong with the seeds this year?

After inspecting a few gardens, it became apparent to me what was going on. In each case, there was a heavy infestation of striped cucumber beetles. They are voracious feeders and are always on the lookout for their preferred food, cucumber vines and related plants such as melons and other vine crops.

In those gardens, the beetles ate every plant they could find that tasted like a cucumber. The sprouts just emerging from the soil were particularly vulnerable which is why it appeared that the cucumbers didn’t come up — they ate every last bit of the tiny cucumber sprouts before the gardener knew what happened. And larger, young transplanted cucumber plants were well on their way of disappearing down the gullets of the beetles. When the vine crops were all gone, they moved over to the bean sprouts and ate those down to the ground. Even older bean plants had lots of holes in their leaves from the beetles.

Striped cucumber beetle.
Striped cucumber beetle.

Striped cucumber beetles are about a quarter of an inch long. They have bright yellow bodies with distinct black stripes running the length of their wings.

This was just the first wave of cucumber beetles, we can expect one or two more generations of beetles to show up later this season.  This generation of beetles will lay its eggs at the base of the plants in the garden. Later they will hatch, feed on plant roots for a while then pupate and emerge as adults later in the season. The next generation of beetles will feed on the underside of the leaves and even chew gouges in the fruits.

Even more important, cucumber beetles carry and will spread bacterial wilt, a serious disease of vine crops. Infected plants wilt and never recover. There is no cure for bacterial wilt once it infects a plant. It’s very disheartening to see your cucumber vines grow and begin to flower only to lose them to wilt. So it’s a good idea take care of cucumber beetles as soon as you find them. Hand picking doesn’t work because they can get away too fast. Instead, apply an insecticide labeled for cucumber beetles, most garden insecticides are effective against them.

Bob

 

 

Planting strawberries

Our strawberry plants were delivered last week, I got them into the ground as soon as I could. After a long ride through the postal system, they were glad to be tucked into our new strawberry bed.

Beginning gardeners may not know that nearly all strawberries are grown from not from seed but from transplants. Strawberry plants reproduce naturally by sending out runners that form plantlets called “daughter plants” that quickly take root. Those new daughter plants themselves will send out more shoots and produce even more daughter plants. Eventually you end up with a dense mat of strawberry plants.

Strawberries should be planted in a well-prepared bed, ideally one that was cleared and tilled at least a year in advance. That will eliminate perennial weeds that will choke out your strawberries before they have a chance to get established. It also will greatly reduce the number of root damaging insects like grubs and wire worms. My new bed is in an area that has been part of the vegetable garden for several years now. I’ve also let the chickens run in this area during the off season. They’ve really kept that spot clean.

In a perfect world, we would plant the strawberries about 18 – 24 inches apart with the rows about two to three feet apart. My row spacing was a bit closer than that because I had more plants than I had room.

You can think of the plants as having three basic parts: the leaves; the crown, which is the center, bulky part; and the roots. The leaves grow from the top of the crow while the roots grow from the bottom. It’s very important to plant at the proper depth. The soil should just cover the roots without burying the crown. That is how a new daughter plant grows naturally. On the other hand, no roots should be sticking up above the soil line exposed to the air. It’s a matter of about a half an inch between too deep and not deep enough. Make sure there is plenty of room in the planting hole so that the roots are straight down and not curled up at the bottom.

At this stage strawberry plants are mostly roots, but the crown and a few leaves can be seen too.

Once your newly planted strawberries establish themselves, they will begin to produce runners and daughter plants. You can shuffle the daughter plants around to a more organized configuration to help maintain rows. That will make it easier to weed and pick later on. Or just let them take root wherever they want.

Pluck the flowers off as they appear, that will keep the plants from wasting its energy producing fruit instead of stronger daughter plants. All those new daughter plants will produce your strawberry crop next year. So the stronger they are, the better your harvest will be.

Keep your bed free from weeds and well watered throughout the growing season. Later, at the end of the season they will need to be mulched. We’ll discuss mulching when the time comes.

Bob

A drawback to growing heirloom tomatoes

Heirloom tomatoes have been all the rage for years now and they are still gaining in popularity — for good reason. Not only do they offer a wide variety of taste and texture, they also come in a rainbow of colors.

On the other hand, there are several drawbacks to growing heirloom tomatoes, I’m not going to go into all of them here right now. Their biggest shortcoming in my experience, is the comparatively small yields compared to modern tomato varieties.

Most of the heirlooms are more finicky and demand more time, attention and sometimes more space than the newer varieties. With all of the additional work that you have to put in to growing them, you would hope that would translate to more tomatoes, but it doesn’t. Many gardeners would argue that the extra taste makes up for the lack of tomatoes. It’s a legitimate argument but I’m not sure if I entirely agree with it. Just about any tomato, even the commercial ones, can taste wonderful if left to ripen on the vine and is harvested at its peak.

If you are growing tomatoes to stash away to use later in the winter, you would be much better off choosing a modern variety that will give you a much higher yield and a more consistent, dependable tomato crop. With all of the things that can happen during a growing season to reduce a tomato harvest, I like to give my crop any advantage I can.

It not unusual for me to put up 50 or more quarts during a typical fall harvest, that takes a fair number of tomatoes. Later, during the winter. those whole, canned tomatoes get cooked down even more and with a few garden herbs, get transformed into spaghetti sauce, pizza sauce, ketchup  and other yummy things — tomato soup is one of my favorites.

Modern tomato varieties produce more tomatoes than heirloom types.
Modern tomato varieties produce more tomatoes than heirloom types.

I still grow a few different heirloom varieties for eating fresh during the summer. There are always plenty to give away to family and friends too. Then, if there are any left at the end of the season, I’ll toss them into the canning kettle with the rest.

I’ve learned through the years that if I want enough tomatoes for canning, I need to grow modern, dependable varieties for my main tomato crop.

Bob

 

 

 

 

Which way to run rows in the garden

Even though the soil out in the garden is still very cold, we can still plant our garden — on paper that is.

There are several advantages to planning your garden on paper or on an app, before setting it out in the ground. The most obvious is you can get a good idea of how much planting material you need such as transplants, seeds or bulbs. And it is handy for calculating how many pounds of soil amendments you may need to add to the soil.

I was once one of those gardeners who never planned ahead very much. When it came to planting, I just picked out my favorite seeds and planted until it either looked like enough or I ran out of material to plant.  I also didn’t pay much attention to which way the garden was facing. Most of the time I had plenty of square footage to use and I could afford some inefficiency. That, however, is not the way to get the most out of a space.

Not long ago, I had a discussion with a friend of mine about which direction garden rows should run.

Sometimes there’s no choice because of the shape of the garden. A long, narrow garden spot may mean the rows have to follow the long axis of the plot. In the past, I’ve had gardens that had an irregular shape so the rows ran in more than one direction because that was the most efficient use of that particular space.

What if you have a square or nearly square garden with one of the sides facing south, should the rows run north and south or east and west?

Imagine the position of the sun in the sky during the growing season. It appears to us to travel across the sky from east to west. As it moves through the sky, the angle of the rays of sunlight changes in relation to the stationary garden plants.

In an east to west configuration,  much more sunlight will strike the south side of the plants than on any other side. In other words, the south side will receive more solar energy while the north side is shaded most of the day.

Rows planted north to south will receive sunlight more evenly. In the morning, the east side of the row receives sunlight. The plant is bathed in sunlight all day as the sun moves until late afternoon when the west side gets sunlight. So the plant receives sunlight on three sides instead of just one.

The cross-hatched areas represent rows of garden plants. The arrow heads represent rays of sunlight. Note how just the south side of the plants in the east to west rows receive sunlight. Sunlight penetrates deep into the rows that run north and south.
The cross-hatched areas represent rows of garden plants. The arrow heads represent rays of sunlight. Note how just the south side of the plants in the east to west rows receive sunlight. Sunlight penetrates deep into the rows that run north and south and contacts more of the surface area.

Not all gardens are situated facing a cardinal direction in an open area. Take for example a southeastern facing garden that is shaded from the afternoon sun. It should have its rows running northeast and southwest to receive the fullest amount of sunlight. Since the garden would get no direct sunlight in the afternoon, it would be a good idea to try to capture as much of that solar energy as possible.

We have a couple of months before our main outdoors planting happens. So now is a great time to sketch out a diagram of of your garden that, in addition to the size and shape, includes direction, and potential sunlight.

Bob

Insecticides work in different way

Winter is a time of planning for gardeners. I decided during the deep, dark days of the dead of winter to take inventory of my fertilizers and pesticides. That got me thinking about some of the different insecticides and how they work.

Chemical insecticides have been around a long time. Fortunately, modern chemistry has eliminated the need for most of the nastiest chemicals we used to use in food products. The lead-based and arsenic-based materials used in the nineteenth and early twentieth century  were made obsolete by more sophisticated chemicals introduced into the marketplace after world war two. Take for example the organophosphates, they were the by-product of chemical warfare research done in Germany during WWII. I remember using some of those products from time to time during heavy insect outbreaks in order to save a crop. I’ll tell you one thing, they sure did the job. Unfortunately, many gardeners used them constantly and on everything. I guess they thought if it was legal and on the market it was fine to use it like that. Sometimes they even eyeballed the amount to use instead of carefully measuring it before mixing. While a few organophosphates are still on the market, most of the harsher ones are no longer available for use in the home garden.

Different insecticides work by different means. For example, the contact insecticides kill when the insect comes in contact with it, either by being directly coated by it or walking across an area on the plant that has been treated.

Stomach poisons work when an insect consumes the material and it enters into the insect’s digestive system. The biological insecticide Bacillus thuringenses  is a stomach poison. It’s commonly use in organic gardening.

Bacillus thuringiensis was the first bacterial insecticide approve for use in home gardens.
Bacillus thuringiensis was the first bacterial insecticide approve for use in home gardens.

Some insecticides are absorbed by plants and are moved to all parts of the plant and remain inside the plant for a relatively long time. These are the systemic insecticides. They are often used on ornamental plants that are not intended to be eaten. I used systemic insecticides many years ago when I had over two hundred roses bushes to care for. The systemics work great for controlling rose pests.

The translaminar insecticides insecticides move just a short distance into the leaves and are not carried through the entire plant. Think of a leaf being constructed of a number of different layers, like a piece of  laminated plywood. A translaminar insecticide only moves into the first or second layer of the leaf. The organic pesticide spinosad is a translaminar material.

Some insecticides work by a combination of two or more of the these modes of action. Often manufactures combine insecticides in order to gain the advantage of multiple modes.

Because an insecticide can act differently on various types of plants, it’s important to closely follow the printed label and not try to extrapolate other uses on your own. This holds true for both conventional and organic insecticides.

Of course we’re not applying insecticides to our gardens right now but it’s not too early to remind ourselves of these things well before the gardening season.

Bob

Medicinal garden growing at Matthaei Botanical Gardens in Ann Arbor

Not long ago growing culinary herbs in a home garden was regarded as an eccentric thing to do and only the most adventuresome gardeners grew medicinal herbs. Things have changed and more gardeners than ever are growing herbs of all kinds.

Seeds for medicinal herbs are readily available in catalogs and online stores making it easy to get started with medicinal herbs.

There are plenty of books and online resources available for anyone interested in growing medicinal herbs but nothing can replace seeing it first hand.

For a wonderful introduction to the world of medicinal herbs visit the Medicinal Garden at University of Michigan Matthaei Botanical Gardens. The folks at Matthaei have collaborated with the U of M College of Pharmacy to develop this garden. There you can see many different medicinal plants growing.

Over forty percent of medicines are derived from plants.
Over forty percent of medicines are derived from plants.

The garden is not organized by genus and species as botanists like to do but rather by human body systems: respiratory, gastrointestinal, cardiovascular and more.  Other areas of the garden are devoted to disorders such as diabetes, infectious diseases, cancer, etc.

Matthaei Botanical Gardens is located near Ann Arbor at 1800 North Dixboro Road, a half mile or so south of Plymouth Road. They’re open daily from 10 am to 8 pm during the summer season.

Bob

 

Grow mushrooms at home in your fridge

There’s a new product out on the market that make’s you want to say:  “Why didn’t I think of that!”

The scientists at a bio-tech company called Genetic Dynamics, have come up with an easy way to grow mushrooms from seed at home.

Head researcher, Dr. Fred Kim, said: “Nearly everyone I know already has some kind of fungus growing in their refrigerator. Our research team  decided to take advantage of that fact”.

Using a combination of conventional plant breeding and cutting edge DNA technology, the scientists created a mushroom that will grow under conditions found in a typical refrigerator.

The new variety called ‘Shrooms’ uses any leftover food as a substrate to grow on. Dr. Kim noted: “The older and more forgotten the leftovers are, the better the mushrooms grow”.

Here are the Shrooms I grew on what I think is leftover mashed potatoes.
Here are the Shrooms I grew on what I think is leftover mashed potatoes.

Walter Tupper, the Executive Chef at Top O’ the Cave Restaurant in Grosse Point Farms, Michigan, uses them almost exclusively in dishes calling for mushrooms. “They have a taste reminiscent of baby portabellas. We obtain ours from a local grower.” he says.

I was able to get a hold of a packet of seeds to try out. I have to admit they are very easy to grow and tasty too!

To order seeds visit the Genetic Dynamics website.

Bob

 

 

 

Damaged Apple Buds

I checked my apple trees  to see if there were any apples left after that freeze we had a couple of weeks ago. There are only a handful of small apples that looked like they could grow on to maturity.

Over 99 percent of the buds were frosted and subsequently fell off the tree. I found a few buds that were still hanging on but, once I touched them with my finger, they fell to the ground.

Apple buds
The tiny apple on top will probably grow into a mature fruit. The small bud below was killed by the frost and has already separated from the tree.

There are other small, growing fruits left on the tree but many of them are deformed. In those cases, the cold temperature killed only part of the bud. They will grow to maturity but will still be gnarled when they reach full size.

We have only a few trees — can you imagine having acres of trees and having to depend on them for your livelihood? That’s the position that fruit growers in Michigan are finding themselves in this year.

The question now is, do I continue to spray? I probably will spray a few times, just to help keep insects and foliage diseases in check.

Bob

Finally Found in the Backyard

I attended the program Scott Kunst owner of Old House Gardens presented last week at the Toledo Botanical Garden.  He sprinkled his informative talk with humor and personal anecdotes. It was well worth the time spent.

During one part of his talk on backyard garden architecture ,  Scott mentioned the fact that there was one original chicken coop left in the city of  Ann Arbor.  He showed a slide of  the structure that was located in  someone’s backyard  on the Old West Side.  Off-handed he mentioned that there was also one original outhouse left in Ann Arbor.   As soon as Scott  said that, I turned to Otto sitting next to me and related a story to him about an experience Judy and I had about 15 years ago.

At that time Judy was designing and maintaining gardens for folks in the area.  One of her clients had a house in the Old West Side neighborhood.  Harold was his name I think.

Harold was in the middle  of re-planting part of his backyard.   He asked Judy to move a lilac bush that was in an unusual spot in the yard.  She agreed and asked me to help with the heavy digging.  We carefully dug out a good sized root-ball and lifted the plant out to be moved.

While digging the last few shovelfuls of dirt out of the hole, I found a marble…then another and another until I had found five marbles.

What we were digging in was the location of a long-forgotten outhouse!  I surmise that when indoor plumbing was installed, the owners tore down their outhouse and planted that lilac over the pit.  This was a very common practice at that time.

I’m guessing the marbles we found decades later must have been lost by a boy who had the marbles in his pocket when he went to occupy the outhouse!  Did he know where he lost them? Probably not.

A boy’s marbles are a precious possession in any era, it was even  more so if  a thing like this happened, say, during the Great Depression. I’m sure he was devastated when the marbles never turned up

Maybe his sister decided to exact revenge on him for teasing her so much. We’ll never know for sure.

The “night soil” had long been turned into rich humus by soil organisms. The lilac roots had penetrated the old pit and the plant was fertilized for I don’t know how many decades before we arrived to move it.

I kept those marbles all this time and never really had a chance to show them to anyone until now.

E-e-e-w-e!! I can't believe he's holding them in his bare hand!!

Those are the actual marbles dug up that afternoon.

Bob