January 29 garden newsletter

I woke up this morning to the sound of thunder, lightning flashing all around and pouring rain.  It sounds like spring but there is still snow on the ground.  It’s an awful, soggy mess out there today and the fog is getting dense and even though it’s supposed to be in the 50’s later I think I will stay inside. 

My computer has been giving me problems and this weekly newsletter may be a little shorter than usual - I’ll see how far I can get today before I get too frustrated.  I have a new computer on the way - hopefully it will get here this week  - and then I have to go through all the problems associated with setting a new computer up and getting used to a new version of windows.  But once I’m through that it should all be fine.

Even though nothing is blooming outside I have a lot in bloom inside right now.  I have geraniums, Euphorbia, African violets, Christmas cactus and abutilon in bloom.  During the last mild spell I brought one of my pots of daffodils inside and it is sprouting.  I am giving them another week on the unheated porch to acclimatize then bringing them into the south window inside.  Hopefully I’ll have daffodils in just a few weeks.  I have been starting cuttings of coleus and will start on geraniums later in the week. 

Yes this is a geranium, unfortunately I don't know its name.

And everyone should have at least one canary singing away in the house as mine are - it makes it sound like spring!  I dump the water from their cups in a plant or two in my office window and some rape seed sprouted in one pot from the water.  The birds now have a few tender green leaves each week from the plant, which they love.

  

Check up for your houseplants

It’s a good time to examine your houseplants for insect pests.  As the days start to get longer these critters get active.  If you see sticky sap on windows, curtains or other items near your plants or the plants and nearby surfaces have a black sooty looking mold your plants probably have one of these insects; aphids, mealy bugs or scale.  These insects excrete a sticky poop from digesting plant sugars and that sometimes leads to the mold growth.  They are sucking the life out of your plants and need to be controlled.

Mealy bugs look like white bits of fluff on the leaves, especially down in the centers of dense plants.  Scale insects look like brown bumps on leaves and stems.  Aphids are small but visible to the naked eye and they can be a number of colors, but are usually greenish indoors.  They are a fat bodied little bug with long legs. 

House plants that are fairly small are relatively easy to treat for insects with this trick.  Cover the pot with a plastic bag to hold in the soil and immerse the plant upside down in a bucket of warm water with a little dish soap added.  Hold all the leaves underwater for at least 5 minutes; more is better but not more than an hour.  Swishing the plant around in the water gently also helps.  Rinse the soapy water off with clean cool water, either in the shower or in a bucket or sink of clean water.  Then place the plants in a room where there are no plants while you clean the area they were sitting in thoroughly.  Clean the windows and adjacent things of any sticky sap or mold, and make sure all old leaves and other plant debris is cleaned up and taken outside before you return the plants.  Examine pots for scale or other insects too.

If the problem was scale insects, those hard shelled bumps on the plant, you should go over the plant leaves and stems with a soft cloth and rub off the scales, as some may survive the dunking.   If you have a large plant with scale and you are patient you can go over the entire plant gently scraping the scale off, even without dunking it.  You will need to make several inspections as I guarantee you will not find all the little buggers the first time.  You can remove heavily infested leaves from the plant; the plant can grow new ones.

For mealy bugs and aphids on plants too large to dunk in water or even on smaller plants you don’t want to dunk, such as blooming plants (soapy water will destroy the flowers) you can purchase a systemic insecticide for houseplants.  Spray type insecticides aren’t too effective, especially on scale and mealy bugs and pollute the air you breathe.

Other pests on houseplants include spider mites and whiteflies.  Spider mites are tiny red moving specks if you shake a plant branch over a white sheet of paper and they leave tiny webs on the backs of leaves and in between leaves and branches.  White flies are tiny specks of white that fly up when you shake or move a plant.  Spider mites are usually bad when conditions are dry.   Give your plants a shower or misting and increase the humidity around them. Dunking the plants can help too.

Yellow sticky traps are used for whiteflies; you can buy them at nursery supply stores.   There are indoor insecticides for white flies and spider mites but use them carefully.    

Another pest that really doesn’t hurt the plants much but can be annoying is fungus gnats.  These look like fruit flies flying around but hatch in your potting medium.  Both fungus gnats and fruit flies can be trapped in an open container of half water and half vinegar with a little dish soap mixed in.  To determine if you have fruit flies or fungus gnats place cut pieces of raw potato on top of your planting medium.  Fungus gnat larvae will come out of the soil into the potato which you can throw away outside.  They will look like dark threads in the potato flesh.  Keep bags of planting medium tightly closed and dry until you use them as they can be a source of the gnats.

Watch that compost

For those of you who buy compost there is new concerns about toxic compost.  There are some chemical herbicides for broad leaved weeds that remain in plants even after they are composted and there is now research that manure from animals which graze fields treated with these chemicals pass the chemical along in manure that gets added to compost.  One research project found that horses eating a commercial big name brand of feed actually had the chemicals in their manure. The feed products tested positive for the pesticides.  It’s not clear yet whether the feeds were accidentally contaminated or as the research hints- the feeds were just made from products treated with these persistent chemicals.

The chemicals in question are actually advertised to be safe if animals graze treated pastures and don’t seem to be posing a problem for animals when in feed.  You can bet that if animals were experiencing health issues that the major feed manufacturers would be more concerned.  However the chemicals do cause major problems for garden plants even after manure and treated plant debris have been composted for several months.  When the compost is added to gardens the plants experience curling leaves, deformities, poor growth and other pesticide poisoning symptoms and may die.

The chemicals that seem to persist forever are picloram and clopyralid which are present in several broad leaf weed killers on the market now.  Also aminocyclopyrachlor, marketed as Imprelis, which killed so many trees a couple years ago, has the same persistence.  The pesticides are not generally for sale to homeowners but are used by farmers and commercial lawn care companies. The pesticide labels do state that treated plants should not be composted.  The pesticides are sprayed on grasses and kill only the weeds (or your trees).

The problem is this.  Commercial composting places collect grass clippings, manure and other organic matter for composting and have no idea if the plant products have been treated with a pesticide or if animals that produced the manure have been grazing pesticide treated pastures or have been fed commercial feed tainted with the products.  .

Some compost facilities are now routinely testing their products because of many lawsuits associated with bad compost applications.  But if you buy compost or manure it pays to be a little cautious.  Ask if the compost or manure has been tested for pesticide residue.

It’s possible that even if you use manure produced on your farm from animals you know didn't graze treated pastures that they may have received those persistent pesticides in a commercial feed you fed them and the manure could be toxic.  You won’t know the manure is toxic unless you have it tested and unless a compost facility tests their product they won’t know if they used tainted manure either.

Making your own compost for the garden is always the safest bet.  If you are composting most garden plants and household food scraps you know that they weren’t treated with broad leaf weed killers.   If you collect lawn clippings or leaves only from lawns that aren’t treated for weeds you are safe.  Manure from organically fed animals is safe as is manure from animals fed primarily on untreated pastures and whole grains rather than commercial feed.   

Compost is still wonderful for the soil and a wonderful way to re-cycle and I don’t want you to fear using compost.  But be a little more cautious with what you compost.  If you experience plant problems soon after applying compost or after planting them in compost enriched soil you may want to remove the compost or transplant the plants.  

Some quirky fun information

Oh what fun some researchers must have.  Some recent research published has detailed how dung beetles navigate.  Dung beetles come out at night and the male beetle seeks manure or dung.  When he finds it he rolls up a ball of it and rolls it to a female who then mates with him and uses the ball of manure to lay her eggs in. That’s how we got the tradition of presenting our loves with candy on Valentines Day by the way.

What researchers wanted to know was how the beetles rolled their manure balls in a straight line right to the females when it was dark outside.  It seems that the beetles use the stars, specifically the position of the Milky Way, which appears to the beetles as a band of bright light, to navigate. They found this out by putting little blindfolds on the beetles outside and by transporting some beetles to a planetarium where they could manipulate the night sky. 

They also found that the straighter and faster a boy rolled his gift offering the more success he had winning the girl.  First come, first served I guess.  Hmmn.  Dung beetle races in the planetarium are considered a good use of research dollars.   Thank God this research was done in Sweden.  And the races were actually filmed, maybe a movie will be made soon or maybe the mob will buy the films for betting purposes.

What wasn’t explained in the report I read is how the boy beetles knew where the girls were in the first place.  To roll a ball of poop toward them they had to know where the girl was.  Do they always line up in a certain relationship to the Milky Way?   Do they wait a respectable distance from the manure heap?  I am sure we need to explore this fascinating behavior more.

Hurry spring!

Stay dry you guys and curl up with a good dung research report.

More Information

Terrariums are really hot this year and I have seen some amazing landscapes in miniature an so many cute plant holders and terrariums are on sale now.  Read more about terrariums here.

While winter keeps most Americans from gardening outside there is some gardening you can do inside that will satisfy your desires both to plan and plant. Miniature landscapes in terrariums or dish gardens are popular right now and they let you combine unique, beautiful containers with exotic to common plants for simply stunning effects. The possibilities are endless for this hobby and even children can design and plant terrariums and dish gardens. Read more here

http://www.examiner.com/article/create-a-beautiful-terrarium

Your plum trees versus black knot

            Winter is the perfect time to scout for black knot in plum trees.

            Posted on January 7, 2013 by Gretchen Voyle, Michigan State University Extension

Black knot is a fungal disease that strikes fear in the hearts of owners of plum trees. It doesn’t matter if they are edible plums or the decorative, landscaping variety, the trees could be fatally affected. Since twigs and branches are easily seen during winter, it is a good idea to check any plums for galls or swollen growths. Michigan State University Extension horticulture educators and Master Gardener hotlines receive many calls about black knot when the leaves are off the trees.

Black knot causes black, corky, swollen growths to form on branches, twigs and occasionally trunks. The nutrient and moisture flow is cut off to the branch that extends beyond the black knot. The spread of the disease has to do with suitable hosts and humid weather during the growing season.

Host trees are plums and occasionally cherries. Very susceptible edible plums are ‘Stanley’ and ‘Shropshire.’ For ornamentals, purple leaf plum and sand cherry are often targets. Edible plums that are moderately resistant to black knot are ‘Damson’, ‘Bluefree,’ ‘Shiro’, ‘Santa Rosa’ and ‘Formosa.’ Japanese plums are generally less susceptible. ‘President’ is the only type of edible plum that is considered highly resistant.

Black knot takes several years to develop. In the first year, small, light brown swellings are visible on the current year or last year’s twig growth, which will be towards the ends of the branches. By the next year, the swellings have grown and become olive green with a velvety appearance. During this year’s growing season, the galls swell and turn black and become misshapen. As the nutrients and moisture are cut off to the twig, the twig could become curved or bent at the location of the gall.

When black knot is found, there are two choices: remove the tree or attempt to treat it. Treatment may remove a large quantity of the branches if black knot is severe. During the winter, the galls need to be pruned out. Prune at least 6 inches away from an existing gall into healthy wood. This may leave very few branches, so this may be the point when deciding whether to keep the tree needs to occur. Burn or bury the pruned black knot wood. Do not drop the pruned galls on the ground. The galls can still spread spores during the growing season. Do not prune during the growing season because the fungal spores can be spread around at this time.

Using a fungicide is recommended only for trees with severe fungal problems or valuable trees. Apply the fungicide when the trees are dormant in the spring – when there are no green buds, leaves or flowers present. Then, spray again when the flower buds color up. The fungicide is to prevent more problems; it cannot cure it. Use a fungicide that has an active ingredient of chlorothalonil or thiophanate-methyl. For many places in Michigan, it will be easier to find a fungicide with chlorothalonil. Be sure to follow the directions. The tree should be sprayed each spring following the timing given above.

Some of these plum varieties are just trouble waiting to happen. This is a very difficult fungal disease to eliminate, but for smart gardeners looking for replacement trees, they now have an idea of what not to select.