25 December 2012

Tuberous Begonias - A Christmas Gift

Tuberous begonias come with many varieties of leaves and flowers.  This plant was first hybridized in 1870 from other species gathered in the Andes mountains.  They are grown in the landscape as well as in pots.

Tuberous begonias need bright, indirect light all day, but a little morning sun or late afternoon sun is fine.  They like evenly moist, well drained soil.  They do not like the soil to dry out.  Begonias want a little dormancy in the winter, so cut back on watering in the winter.  They are also frost-tender, so keep them out of freezing or near-freezing weather.

In spring, begin fertilizing with a diluted, complete liquid fertilizer every two weeks, or once or twice with a slow-release fertilizer at the beginning of the growing season.

Make sure begonias have good air circulation, but keep them protected from wind.  Sometimes poor air circulation leads to a fungal disease called powdery mildew.  As its name suggests, it will look like a white powder covering the leaves.  As a preventative, you can spray a mixture of one tablespoon of baking soda per one gallon of water once a week.  Once the fungus develops the only treatment is a commercial fungicide.


Peperomia - A Christmas Gift

I decided to give a few plants as Christmas gifts this year - it makes sense, since I picked up several plants out of people's trash and rehabilitated them.  The plan was to repot them into something nice and write about how to take care of them.  I also have some packets of slow-release fertilizer I thought I would include with the card.  Here are my care instructions for Peperomia:

The Peperomia plant is a tropical house plant grown for its interesting and variety of foliage.  Looking at its slightly succulent appearance, you would think that it comes from an arid region, but, in fact, it lives in the shade of South American rain forests.  Although the flowers are usually insignificant, there are numerous varieties of this plant that have different shapes, colors and textures of leaves.

Being a tropical understory plant, Peperomia like bright, indirect light and they are very comfortable in a cool environment (65-75 degrees), like most homes.  They like a more humid environment, so, like other house plants, keep away from heating vents and you may want to set them on a gravel tray with water or mist them regularly to increase humidity.

When watering Peperomia, they like the soil to stay moist, but they don’t like to be overwatered.  Signs of overwatering include wilting and raised scab-like protrusions on the leaves.

Beginning in the spring, they will need to be fertilized regularly either with a diluted liquid fertilizer every two weeks, or with a slow-release fertilizer a couple of times during the growing season.

There is little need to repot Peperomia often.  They are shallow-rooted and like to be slightly rootbound.  But when you do repot, there are a few things to remember:  either remove the plant from its pot, root prune and repot, adding organic matter such as compost;  or repot into a slightly larger pot, adding compost or other organic matter.

19 December 2012

Are Poinsettias Poisonous?

A few days after I posted about poinsettias, I realized that I didn't address an issue which I wanted to and other might want to know about - are poinsettias poisonous?  The answer is no, generally speaking.  Being Christmastime, a lot has been published recently about this topic, and everyone agrees that it is not.  That doesn't mean it's completely safe.  Poinsettias, as well as all other euphorbias excrete a milky sap, called latex, when cut.  This latex can be an irritant to the skin and cause damage if you get it in your eyes.

So why do more than half of us believe this?  In 1919, a two-year old child died and the cause was incorrectly determined to be poinsettia poisoning.  If someone does managed to eat a number of leaves of the plant, there will probably be an upset stomach and vomiting, but apparently they taste so bad, it seems like it might be too difficult to eat enough to do any damage.  A 50-lb. child would have to eat more than 1.25 lbs. of poinsettia bracts (500-600 leaves) to excede the experimental doses, according to the POISINDEX Information Service.

So, there's no need to worry about eating the leaves.  Having had other euphorbias in the past, my biggest fear was of the latex, but everything will be fine, if you don't get it in your eyes.  Merry Christmas everyone!

(source: snopes.com)

16 December 2012

Poinsettias

I've been working on a lot of different articles lately, but I put those aside to try to write about something more seasonal - Poinsettias.  Named for botanist and Charleston native, Joel Roberts Poinsett, who introduced the plant into the US in 1825, the Poinsettia (Euphorbia Pulcherrima) has become synonymous with Christmas.  Almost everybody has one this time of year, but does everyone know how to take care of them?  And what to do with them afterward?

Poinsettias are tender, tropical plants, and as such, do not do well at our house as a rule.  But since my in-laws gave us one this year, I'm determined to take care of it the best that I can.  So I set out to learn more.  During the winter, poinsettias need about six hours of bright, indirect light.  They tolerate temperatures between 50 and 70 degrees, but they should avoid drafts if at all possible.  They like moderately moist soil, but they can't tolerate standing water - that can happen if you water your poinsettia while it's sitting in the decorative foil it came in.  Take it out to water and make sure all of the water has drained before putting it back in the foil.  While it is at its most colorful, showing off its red (or another color) bracts - modified leaves, not flowers - there is no need to fertilize.

It is now spring, and if you still have your poinsettia, you will notice that the colorful bracts have died back.  Prune the plant back to eight inches, and once nighttime temperatures stay above 50 degrees, take the plant outside - remember, it need bright, indirect sunlight.  At this point you can begin fertilizing every 2-3 weeks with a complete fertilizer, i.e. 10-10-10, and in June transplant into a pot about 2-3 inches larger than the one it is in, making sure to add lots of organic matter like peat moss, leaf mold or compost.  If you want to prune it again, you can, but do it before September 1st.  When nighttime temperatures dip to 55-60 degrees, it's time to bring it back in.  Now all of that was easy.  Now it's time to get it to rebloom.

So, you've really committed to this plant, huh?  If you thought it needed lots of attention before, just wait.  Poinsettias, like other Euphorbias are what's called "short day" plants.  Some plants need shorter days - actually longer nights - to initiate the flowering process.  With houseplants being in the environment they are in, they don't experience the natural change in sunlight, so they have to be given it artificially.  Begininning the first week of October, poinsettias need 14 hours of continuous darkness each night for 10-12 weeks.  That means moving the plant to a dark closet, or putting a box over them from roughly 5pm to 7am every day.  During the day, they will need 6-8 hours of bright indirect light.  If you have done all of this, your poinsettia should begin to bloom - form colorful bracts - in November or December, depending upon the cultivar.

Wish me luck with my efforts with Poinsettias, and if you want more info on this or other "short day" plants visit HGIC 1561 Poinsettia or Wikipedia's article on photoperiodism.

12 December 2012

Florida Betony

As the days began to cool off, I started making plans to control the cool-season annual weeds in our lawn.  While I was waiting for the proper time to apply preemergence herbicide, a problem weed reared its ugly head - Florida betony (Stachys floridana).  Also known as rattlesnake weed, this cool-season perennial appears in lawns before other weeds, growing from an underground tuber that gives it its nickname.  It is a very aggressive weed, having made its way from Florida in the 1940s or '50s, and will thrive in your yard during the winter as the lawn goes dormant.  There's nothing worse than seeing a brown, dormant lawn, with about 10-20% covered with this green weed.

Not much is known about how this plant reproduces by seed - it is thought that it mainly spreads by growing new tubers - but before we moved in here, this house was vacant for at least two years, so I'm sure a minimal maintenance of the yard provided the opportunity for this weed to spread.

There are several 3-way broadleaf herbicides that can be used for spot treating Florida betony.  In addition, lawn weed sprays containing Atrazine will control this weed.  I'm not a fan of spraying chemicals on the lawn, but with as much as we have here, it might be necessary.  I'll probably spend some warm winter afternoons spot treating weeds in the lawn, but not before I figure out which herbicides to use at:  HGIC 2313 Florida Betony

05 December 2012

Imaginary Call to the Master Gardener's Office

    "I have this weed that grows only in the winter in my St. Augustine grass yard! It's really annoying because it grows real low to the ground and forms mats.  The leaves are like little ears (lobed) and I don't see any flowers.  When I try to pull it up, it sticks me in the hand!"

I recently took an online Master Gardener continuing education / re-certification course in which the previous scenario was given to us.  Before taking this class, there is good advice I could give this person without knowing exactly what the weed is.  It is a winter annual so, a properly-timed application of preemergence herbicide will control it.  Hand-pulling larger plants (with gloves) is an option.  Also, a broad-leaf herbicide for St. Augustine lawns would work if you missed applying a preemergence.  But we were given an additional resource to identify this weed - Turf and Weed ID.

I've only played with it a few times, but this site helps identify a number of grassy and broad leaf weeds and sedges, if you can describe them accurately.  Some of the questions you needs to answer are whether it is a grass, broadleaf or sedge, its growth habit, bulbous or fibrous roots, leaf characteristics, etc.

So, let's use this tool to solve our current problem.  The first decision we have to make is the type of plant.  The fact that the leaves are lobed tells us that it is a broadleaf weed - we're down to about 50 choices.  The fact that it grows only in winter suggests that it is a winter annual - that cuts our choices in half.  We used the fact that the leaves are lobed to determine that it is a broadleaf, which narrows our possibilities down to about seven.  This person said that it grows low to the ground, so, after choosing "prostrate" as its growth habit, we are left with only one plant - lawn burweed (Soliva sessilis).

I didn't know what this plant looked like, but I was familiar with it nevertheless.  I used to walk around barefoot a lot and I won't forget the feeling of stepping on burweed.  Over the years I avoided certain yards and wear shoes outside all the time now, so it's not an issue anymore.  It is a winter annual, but as the weather warms in the spring, it begins to grow rapidly, producing spiny burs.

An ounce of prevention goes a long way.  A healthy, robust lawn will outcompete this weed, reducing the amount your yard.  Burweed can become established in areas where the turf isn't very thick, so good lawn care is important.  A number of different herbicides will control the spread of lawn burweed.  Postemergence herbicides are more effective on this weed during the winter, when the plant is small.  If you use them on the plant during the spring, it may be harder to kill.  It may also give the plant a chance to produce its burs, in which case, a preemergence herbicide will be necessary to further control the spread of this plant.  For more detailed information and herbicide recommendations, please see HGIC 2323 Lawn Burweed.

02 December 2012

Holiday Tour of the Recycling Center

We did this three years ago, but I still think it's really interesting.

This past Tuesday Charleston County Recycling invited neighborhood volunteers to a reception and tour of the John L. Jencks Recycling Center at 13 Romney Street. As a neighborhood volunteer - I put out a sign every two weeks - Robin and I got to go on the tour. Putting out a sign doesn't seem like much of a job, but overall, it has increased recycling rates from less than 30 percent to just over 50 percent. Enough about that - let's get to the tour.

For a slide show of the tour, please click here.

When trucks arrive at the recycling center, the first thing they do is get weighed. After that they dump their co-mingled loads of plastic and metal. Local inmates load all of this onto a conveyor, which takes it into the building - you're going to see that word (conveyor) a lot.

Once inside the building, there are magnets that separate steel and aluminum, while workers separate plastic and glass. Conveyors dump steel and aluminum into hoppers and crushed into small cubes, which contain about a thousand cans. About a hundred cubes are bundled together for transport - pictured. Glass is separated by color and conveyors toss them into stalls outside - Companies buy recycled glass and use it to make other products.

Other products are sorted and bundled separately - plastic milk cartons are recycled into more milk cartons, while soda bottles and the like are made into carpeting. Paper is made into more paper.

Charleston County Recycling picks up most items at the curbside. A few things that they recycle, but not curbside, are CFLs, corrugated cardboard and electronics. For a complete list of recyclables, click here.