Home Gardener Headlines - Spring 2012

Dear Home Gardener,

What bizarre weather patterns we're having!  At least we have gotten april showers, but only after March drought put us into a huge water deficit before the season even began.  If your plants are thriving after record summer heat last year, wrecking storms last fall, the up-and-down snowless winter, and our early parching - congratulate yourself!

If not, in the following pages you'll find our survival tips for Weird Weather and Other Garden Conundrums, Version 2012.  Perhaps some of these tips will help you salvage and support your lawns and landscapes until Mother Nature returns to more seasonal temperature and precipitation cycles.

Happy Gardening!

Beth Finlay
Master Gardener Coordinator

Nancy Bosold
Extension Educator

Mulching Tips

Fluff!  Before ordering more mulch for your landscape, use a rake or long-handled cultivator to loosen and freshen the mulch.  Mulch can get compacted to the point where it sheds water and prohibits air exchange in and out of the soil.  And you may find that you already have enough mulch without ordering more.

Moisten!  Mulch, in addition to discouraging weeds and looking nice, provides a "blanket" over your soil.  the trick is to use that blanket to keep moisture IN, not OUT.  Wait till after a soaking rain to apply mulch, or if feasible, soak the soil well with a hose before mulching.

Let your trees go naked!  The bark of trees is meant to be a hard barrier between the inner tissues and the cruel world.  If you pile mulch against stems or trees, the bark softens and rots, exposing the plant to insect and disease damage and to rodent chewing.

Less is more!  A total mulch depth of 2-3 inches is plenty to protect plants and provide an attractive backdrop for plantings.  Any more will restrict water and air movement to the roots of your plants and will actually compromise plant health.
Written by Beth Finlay, Master Gardener Coordinator, Penn State Extension in Berks County

Emerald Ash Borer (Bad) News

On Wednesday, March 14, 2012, PA Department of Agriculture confirmed that Emerald Ash Borer (EAB) has been detected in Warrington, Bucks County.  The infestation was first observed by an arborist who contacted Penn State Extension.  Department of Agriculture entomologists collected specimens at the site on March 12 and positively identified larvae taken from infested trees.

Emerald ash borer (Agrilis planipennis) is a threat to all ash (Fraxinus) species in Pennsylvania.  It is estimated that EAB has killed more than 50 million ash trees since its original detection in Michigan in 2002.  Fifteen sates and two Canadian provinces are infested.  In Pennsylvania, EAB has been moving east since the original detection in 2007.  The detection in Bucks County is the first in southeastern Pennsylvania.

Penn State's Emerald Ash Borer website (http://ento.psu.edu/extension/trees-shrubs/emerald-ash-borer) is an excellent portal to research-based fact sheets, pictures, and reports on this important insect, including a link to the national EAB website (http://www.emeraldashborer.info) as well as links to information from states such as Michigan which have the most experience with the devastation caused by this insect.

An overview of the basic biology of EAB can be found in the US Forest Service Emerald Ash Borer Alert (http://ento.psu.edu/extension/trees-shrubs/emerald-ash-borer/more-information/USDAFS_EABPestAlert.pdf/view).

The "Frequently Asked Questions" feature (http://ento.psu.edu/extension/trees-shrubs/emerald-ash-borer/frequently-asked-questions) at the Penn State site provides information to concerned property owners.  Finally, A Homeowner's Guide to Emerald Ash Borer Treatment (http://ento.psu.edu/extension/trees-shrubs/emerald-ash-borer/factsheets/EAB2955.pdf/view) provides guidance for property owners who are considering a do-it-yourself approach to treatment.

If you do not have ready access to these websites, paper copies of the information are available from the Penn State Extension Office.

We almost certainly will find this pest in Berks County one day but until then, do not carry firewood from other areas into Pennsylvania or from neithboring counties into Berks.
Written by Scott Guiser, Extension Educator, Penn State Extension in Bucks County

Watering Tips

Water deeply and occasionally.  This applies to trees, shrubs, perennials, and even lawns--except for new grass seed, which must be kept moist continually until it germinates.  Water must get well down into the root zone of plants to be effective.  Shallow, frequent watering will encourage fine roots to migrate to the surface, where the first heat event will fry them.

Water when a probe shows dry soil a few inches below the surface.  Let a hose run in a slow enough trickle that water is being absorbed and isn't running away into the street or onto non-productive areas.

Water under mulch.  It can take gallons of water to saturate through a mulch covering, before any moisture reaches the soil.  Make the most of limited water by applying it directly to the soil where possible.  This can be achieved with soaker hoses between soil and mulch, or by watering into the bare areas around tree trunks and stems of plants.  The water will run along the soil surface beneath the mulch.  The mulch covering will help keep the soil moisture from evaporating before the roots can absorb it.

Water at ground level.  Watering near the ground rather than over the tops of plants makes the most of your water, and keeps foliage dry.  This is important because moisture on foliage promotes the development of fungal disease.

Use hoses or watering cans instead of sprinklers.  With the exception of some lawn applications (especially new seedings), sprinklers are too wasteful.  Targeted watering directly where it is most needed increases the chances of root absorption and reduces evaporation and run-off.

Maximize your water use by planting "thirsty" plants in a common area, and more drought-tolerant plants elsewhere.  And look for that "drought tolerant" label.  some plants will endure drought cycles without supplemental watering.
Written by Beth Finlay, Master Gardener Coordinator, Penn State Extension in Berks County

Guilt-Free Gardening

Gardening, like any other hobby or industry, has its fads and trends.  Do you ever feel pressured to change what you’ve always done, to “keep up?”  The spouse of one Master Gardener, after observing groups of gardeners in action, commented, “I never knew gardening was a competitive sport!”  Well, it needn’t be.  if you are more oppressed than enticed by the following trends, let’s put them in perspective.

Native Plants:  Is it important to include native plants in a landscape or garden?  Sure, we need to support our native flora and fauna, and these plants will do it better than imports, but it’s not necessary to abandon your present plantings.  Do a little reading and identify just one or two native plants to include among your future purchases.  If we all did that, our native pollinator insects would thank us!  If your favorite shrub is an exotic, ease your guilt by adding a native nearby, and enjoy the virtues of both!

Heirloom Vegetables:  You’ve come to rely on your favorite hybrid tomatoes and new improved melons, but now all the news is heirlooms.  Are they really superior?  Perhaps in some ways—some swear by the “true tomato” taste of earlier varieties, and some enjoy the unusual colors and shapes of these ancestors.  But hybrids are successful for a reason.  They tend to be hardier and more disease resistant and may require less attention overall.  You don’t have to avoid those hybrids you’ve come to love, but try an heirloom or two for fun and comparison.  You may find a new favorite, and mixed in among disease resistant plants that aren’t sharing pathogens, they may thrive as well as the modern cultivars.

Technicolor Splashes:  Bright chartreuse, vivid orange, passionate purple, sometimes all together!  Our choices and preferences in plant colors have certainly expanded.  But if you enjoy the soft, restful pastels (think Monet) or just the occasional accent of color, don’t feel you have to follow this trend.  If you’re enticed but unsure, be adventurous in a container planting, and see if the newer colors have a permanent place in your gardens or should just visit for a season.

Grow Your Own Food:  This is a wonderful family hobby or retirement diversion IF you truly enjoy it.  But vegetable gardens do take time and attention, and they will need water just when you need a vacation.  If home vegetable growing is not for you, you can still have a local influence by supporting your area farm markets, orchards, or CSA (Community Supported Agriculture) farm cooperatives.  And if you’d like to share the abundance, buy a bit extra to share with your local food bank.

Appreciate the new trends, experiment as you like, but in the end, your garden can and should reflect what you most enjoy!
Written by Beth Finlay, Master Gardener Coordinator

Earthworm Mounds in Lawns

What is causing all these hard mounds in my lawn?  The lawn is so lumpy it’s hard to walk on, and it rattles my teeth when I mow!

After receiving many calls and emails about lumpy lawns during March, I decided to investigate my own lawn.  Sure enough, as I walked around there were many hard, irregular lumps throughout the lawn area.  Dry conditions made those lumps even harder and more noticeable underfoot.  The lumps were one to three inches around with no noticeable hole opening to the surface.  The soil in many of the mounds looked like it had been squeezed from a tiny tube of toothpaste.  When I dug under the mounds, I found holes the diameter of a pencil, and I even found ¼- to ½-inch plugs of what looked like chewed grass.  I even found some small (1 to 1.5 inch) earthworms in and around the mounds, but didn’t see anything large enough to make a pencil-sized hole.  I tried to excavate the hole and follow it, but couldn’t find the bottom or a creature.

I suspected that what many of us were seeing were earthworm mounds, more specifically mounds made by the subsoil-dwelling earthworms, like nightcrawlers.  So I did a little research to find out about the habit of these extremely beneficial creatures.

There are over 1,000 species of earthworms, but they can be grouped together into three main groups:

1.      Litter dwellers that live in forest litter or plant debris on top of the ground, and don’t ingest a lot of soil.

2.      Topsoil dwellers that live in the upper three inches of soil, feeding on partly decomposed organic matter.  They burrow horizontally and fill their burrows with excrement (which is a mixture of digested soil and plant residue).

3.      Subsoil dwellers that live in permanent vertical burrows that can be five to six feet deep. They feed on plant residue on the surface, capping their burrows with plant-residue plugs.  They deposit their excrement (which is a mixture of plant residue and soil) in piles on the soil surface.  Nightcrawlers belong to this group.

Bingo!  So why are there so many in your lawn?  Earthworms thrive in untilled areas, and they do best where the soil is moist, moderate in temperature, neutral in pH, and loamy in texture.  They also need a constant food supply of plant debris.  Lawn areas provide many of the things needed by earthworms:  partially decomposed clippings and thatch provide plenty of food; the lawn is undisturbed by tillage; and the soil conditions are usually right.  So, the environment under most home lawns is ideal for these hard-working compost factories!

Mounds are most noticeable when nightcrawlers are most active in early spring and again in the fall.  Coincidentally, in early spring the grass coming out of winter isn’t growing fast enough to cover the mounds.  And this spring the drier weather meant that rain didn’t help erode the mounds or help squash them down.  In the summer earthworm mounding activity slows down.  By then thicker grass covers mounds and more frequent mowing helps push the mounds down, especially if the soil is moist.

To level the mounds, you could use a power rake or dethatching machine.  This is best accomplished during the fall so you won’t create weed problems.  Some people use a lawn roller after a rain to push the mounds down.  If you do that, you may need to aerate in the fall to offset compaction from rolling.

Patience is the key, as the mounding activity will become less noticeable during the late spring and summer.  No need for treatments and a few lumps are a small price to pay for the benefits provided by earthworms.
Written by Nancy Bosold, Extension Educator, Penn State Extension in Berks County