Friday, August 10, 2018

Biological Control of Purple Loosestrife

It's the height of summer, and the Purple Loosestrife in my detention pond is in full bloom.

However, when I say full bloom, I mean FULL bloom.  For here in North America, Purple Loosestrife, aka Lythrum salicaria, is a highly invasive plant.

Just some of the Purple Loosestrife in my detention pond
There's no denying that this particular invasive is a strikingly gorgeous plant.  Hailing from Europe and Asia, this wetland plant has been prized throughout history as an ornamental in the garden in addition to its medicinal use for gastrointestinal ailments.

Overseas, there are a number of cultivars of Purple Loosestrife.  'Blush', which has pale pink flowers and 'Feuerkerzeze', which has sterile, vividly-colored double flowers, have both won the British Royal Horticultural Society's Award of Garden Merit.

Hummingbird Clearwing Moth on Purple Loosestrife
In the 1800's Purple Loosestrife was introduced into North America either accidentally as seeds floating in ship ballast water or intentionally as an ornamental.  In the years that followed bee keepers spread it to other parts of North America, as its many flowers offered an abundance of nectar for the bees.  It has since spread into most US states and up into Canada.

While bees and other pollinators love the flowers, unfortunately there are not many animals or insects here that eat the plant to keep it in check.  Purple Loosestrife invades wetlands, crowding out native plants.  It forms dense, impenetrable stands that are unsuitable for native wildlife such as ducks, frogs and turtles, and these animals are often forced to relocate. 

Once Purple Loosestrife is established in an area, it is nearly impossible to get rid of due to the immense number of seeds each plant produces.  A mature plant can produce millions of seeds, and these seeds remain viable in the soil for years.  It can also re-sprout from any pieces of roots left in the soil or water.  Managing this invasive plant by manual removal, burning, cutting, herbicides, and water management have all been tried... and found to be either too difficult, too costly, or environmentally unsuitable. 

So what to do about this plant?  In the mid 1980's, biologists began to search for what is usually the last resort - a biological control.  Biological controls are very tricky, as we have found out over the years.  Deliberately introducing something new into the environment can go terribly wrong.  Asian ladybugs that were released to fight aphids have now edged out many of our native ladybugs.  Our largest native moth, the Cecropia silk moth, is now under attack from a parasitic fly that was meant to control gypsy moths.  And most of us know what happened with Kudzu, aka 'the vine that ate the South'...

Thankfully, testing for a biological agent is now much more rigorous.  Scientists considered over 100 insects overseas that were known to feed on Purple Loosestrife.  Several were thought to have possibility, and extensive testing began in Europe.  The insects were exposed to many North American species of plants to make sure that they would not end also attacking our native plants if introduced here.  In 1992, after six years of testing, the US Department of Agriculture approved four insects for release into the US for the control of Loosestrife:  two leaf-eating beetles (Galerucella calmariensis and Galerucella pusilla), one flower-feeding weevil (Nanophyes marmoratus), and one root-boring weevil (Hylobius transversovittatus).

Hylobius transversovittatus on Purple Loosestrife
(photo via wikipedia)
Would these biological controls work?  In the mid 1990's the U.S. Fish and Wildlife Service began releasing the leaf-eating beetles in various suitable areas, including two National Wildlife Refuges here in Massachusetts.  Between 2000 and 2008 the state government teamed up with various wetland conservations programs to release more beetles in Massachusetts through the Purple Loosestrife Biocontrol Project.  Beetles were released at 43 sites throughout the state, starting with Turner's Pond in Walpole, just a few towns away from me.  Within four years, Turner's Pond saw an 80% drop in Loosestrife plants.  This biological control worked!

However, to be a true success, the release of the beetles should not cause any negative effects on the environment.  Studies have found that the beetles do sometimes feed on two similar native plants, however they prefer Purple Loosestrife, and no serious problems have been reported.  Monitoring will continue, but so far this is one biological control that is a success!

Now I just need some of those beetles to fly over to my detention pond...

With all this Purple Loosestrife, I have quite a good meal for them!

Sunday, July 29, 2018

In the Jungle

I feel like I've hardly been in the garden the past few weeks between traveling, visitors, and the weather.  June ended on a heat wave, with temperatures soaring up to 97°F (36°C) into early July.

While that might be normal temperatures down South, my body has now acclimated to the Northern winters and cooler temps.  Thankfully the highs have since dropped back down into the 80's, which is more normal for summer here. 

Daylily - possibly 'Frosted Vintage Ruffles'
Hopefully now that it is cooled down and I am done with my travels, I can finally give my neglected garden some attention.  It is turning into a overgrown jungle.

the front jungle, ah, I mean garden
My parents recently visited, and my dad joked that he should have brought a machete to help me get through my garden.

the overgrown greenhouse garden
I have my work cut out for me!  At least as I start the weeding and pruning, there are so many pretty blooms in the garden to enjoy.

Clockwise from top: Gardenia 'Frostproof', coneflowers, Calendula 'Snow Princess', Daylily 'Stephanie Returns', Lonicera sempervirens 'Tangerine Princess', bee on Salvia 
The garden is also full of birds, butterflies, bees, and an unfortunate number of baby bunnies.

a perching Hummingbird - arguably cuter than the bunnies?
I've started seeing Monarch butterflies almost every day here - a positive sign.

Monarch butterfly on milkweed
Well, wish me luck!  It's back to the weeding and pruning... and staking.

Happy gardening!

Saturday, June 30, 2018

Fortress of Plantitude

Another spring, another project here at the Red House Garden!  I was lamenting that our fenced-in gardens were in the backyard, while our sunnier front yard was open to the feasting of the critters.  My husband was lamenting the patch of lawn in the front yard that was compacted and not doing well...

Time to tear up some lawn and build a critter-proof garden instead!  But, being in our front yard, we wanted to build something extra pretty.

Our idea was to build a garden that looked almost like a gazebo, but with an open roof.  We hit the drawing board, and this was what we came up with.

octagonal fenced-in garden
We had thought to build this during spring break, not realizing just how ambitious a project this was.  It ended up taking about a month to build the bulk of it.

We first built our octagonal base in the driveway.

Then came marking, digging, and filling with a paver base sand to stabilize our base.  (A little child labor was very useful, too, as you can see.)

Then we built the middle base.

Lots of leveling.

We covered the bottom with wire hardware cloth to keep voles and groundhogs from digging underneath.

4x4 posts were attached at the corners with metal brackets.

Lots of pieces of wood were cut to form the sides.

At this point, our neighbors started coming around, wondering what in the world we were doing.

Time to build the roof!

Lifting the roof up was quite an adventure.

Much trigonometry was done to find all the angles and lengths to cut throughout this entire project.  I wish I had written and kept all of the math in an organized fashion so someone could recreate it more easily if they wanted to.

Black landscaping fabric was stapled to the inside of the garden to make sure that soil did not seep out through any gaps.

The garden was filled with soil, and then black wire fencing was rolled out and stapled to the inside of the posts to deter the groundhogs and deer.

A little more paint, some bags of stone for the floor in the middle, a door, and viola!

octagonal garden
Now we just need a good name for our new fenced-in octagonal garden.
The gazebo garden?  The Octagon?  Fortress of Plantitude?

Any ideas?

Happy planting!

Saturday, June 16, 2018

The Easy Care Gladiola

Showy gladiolas elicit strong opinions from gardeners, as they are diva plants in the garden.  Some love their dramatic, tall spikes of bold colors, while others (such as the well-known English gardener Alan Titchmarsh) hate them with a passion.  I personally like gladiolas and enjoy their showiness - but on the other hand, I hate how much work they take.  I have to stake each one in the summer so they don't fall over from their top-heavy blooms, and I have to dig them up for the winter, as they are not usually hardy in my zone.

I don't like gladiolas that much.

Thankfully there are other, easier-going types of gladiolas.  They may not be as showy as those dramatic divas, but neither do they act like it.  They are the smaller, hardier glads, such as the species Byzantine Gladiolus (Gladiolus communis ssp Byzanthinus), which I have in my garden.

Byzantine Gladioli
Native to the Mediterranean area, this gladiolus grows to 2 or 3 feet tall and doesn't need to be staked. It is also hardy up to zone 5, so I don't have to dig them up the fall.  Even those gardeners that say they don't like glads appreciate the gracefulness of this one, which more closely resembles a wildflower than a showy diva.

Sometimes known as Sword Lily, Jacob's Ladder, or Turkish flag, Byzantine gladioli corms (similar to bulbs) are usually planted in fall and bloom their bright magenta flowers at the end of spring through early summer.  They like full sun and well-drained soil, though they will tolerate part shade and even heavy clay if in a dryer area.  Over time they multiply to form nice stands of flowers that I've seen the hummingbirds enjoy.

stands of Byzantine gladioli next to Geranium sanguineum
According to Old House Gardens, less hardy imposters are sometimes sold under the name of Byzantine gladiolus, so you do have to buy them from a reputable source.  (I've always bought mine from Brent and Becky's Bulbs.)  I've grown this gladioli in both North Carolina and up here in Massachusetts and have had great success with it.  I just plant the corms in fall and let them do their thing.

Beautiful gladiolas with little care from me?
That's a winner!

Saturday, May 26, 2018

Salad Success

Ever have a plant that just won't grow for you?  Or even a whole group of plants?  For me, it was greens.  It didn't really matter what type - if it went in a salad, it probably wouldn't grow for me.

Spinach 'Bloomsdale'
Seeds wouldn't germinate.  It would be too hot or too cold.  Slugs ate the lettuce.  Grubs ate the spinach.  Whatever the reason, I never ended up with enough greens for a even a garnish, much less an actual salad.

Corn Salad 'Bistro'
This year, however, I was determined that things were going to be different.  It was going to be THE YEAR.  I sowed early greens in well-prepared raised beds and under the protection of a row tunnel.  I soaked and germinated my stubborn spinach seeds between damp paper towels in a baggie and then planted them in seedling trays indoors.  Lettuce seeds were also started indoors before careful transplanting into the veggie bed.

Did it work?  Did all my efforts pay off?

claytonia, spinach, lettuce, and corn salad
It was a resounding success.

To my delight, this year all of my salad greens grew - almost too well!  I can probably now invite the entire neighborhood over for salad and garnish some pasta plates while I'm at it.

one of many harvests of Claytonia
I grew four different types of greens this spring, and they all did well.  My favorite was Claytonia, also called miner's lettuce after being used by California Gold Rush miners to prevent scurvy.  Native to western North America, it has mild-tasting, succulent type leaves and eventually little white edible flowers.  It was both the easiest green to grow and the most productive.  I couldn't eat it all and started giving bags of it away!

Lettuce 'Four Seasons'
The 'Four Seasons' Lettuce was delicious, productive, and the prettiest of them all, with its beautiful red-tinged leaves.  Corn Salad, aka Mâche, did well and was the earliest of the greens to grow.  Last on the list was spinach.  I love spinach, but it was most notable for both taking the most work to grow and for bolting the earliest in the warm weather.  I did still get quite enough for a salad or two, though.

I call that success!

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