Veggies – Boom or Bust?

August is when the vegetable garden is in full throttle.  If you planted zucchini, you are trying to give them away to everyone you know.  Tomatoes are ripening faster than you can eat or cook into tomato sauce.  And your corn is as high as an elephant’s eye (according to the 1943 musical, Oklahoma).  But, is it?  We’ve had a relatively wet summer in Delaware, so far. Of course, rain is good, but too much can cause problems in the garden.  Tomato plants with fruit cracks can be caused by hot, rainy weather.  Some plants have leaf roll, where older leaves near the bottom, roll up from the outside towards the center, caused by high temperatures and too much pruning.  Various leaf spots are starting to reduce the ability of tomato plants to capture the sun for photosynthesis.  One solution is to be sure to space your tomatoes far enough apart for sufficient air circulation.  Avoid watering tomatoes from the top, which spreads disease spores (although hard to avoid when rain is doing the watering).  Always rotate the location of tomatoes in the garden.  Many fungal diseases overwinter as spores in the soil, so if you have a problem one year, you will probably have it the next unless you plant tomatoes in a different location. Bacterial leaf spot is also a problem on tomatoes and peppers and is favored by rain and high humidity.  You can pick off the worst leaves and/or use copper sprays for large plantings.

My two zucchini plants have succumbed to squash vine borers and look like a wilted mess.  If you catch these borers early, when one or two leaves are first starting to wilt, you can carefully remove the vine borer by making a slit in the stem with a sharp knife.  Sometimes parts of the zucchini vine will even re-root in rich soil.

Corn has thrived in our 2017 summer weather.  I have never seen corn so tall and green! Remember to plant corn in blocks, rather than long straight rows.  Corn must cross-pollinate. Pollen from the top of one corn plant must fall on the silks of a neighboring plant.  That works best when the corn is in blocks.  Plant corn several times during the season, so it doesn’t all ripen at the same time.  Or use different varieties with varying days to harvest.  Corn varieties vary from 60 to 100 days from planting to harvest.

Beans, especially when picked young and tender are one of the best garden vegetables.  Purple beans are fun because they are easy to see and pick.  They do turn green when you cook them.  Can you tell the difference between wax beans and green beans?  One of the activities around my family dinner table was to close your eyes, receive either a wax or green bean, and guess the color.  Statistically speaking, my family is a fan of all beans, regardless of color.  The key to successful green, purple or wax bean crops is multiple plantings.  Beans will produce for 2-3 weeks. If you space out plantings by about 3 weeks, you will always have a new crop to harvest.

Lettuce and other leafy greens, like arugula, kale and spinach are cool season crops.  That doesn’t mean they can’t be planted in the summer, but they will bolt and become bitter more quickly in hot weather.  So, plant multiple crops and harvest them young.

If all this sounds too complicated, here is a solution – buy your vegetables from a local farm stand, a CSA (community supported agriculture where you buy a share at the beginning of the season and receive a box of veggies each week) or from the UD Fresh to You Garden.  The UD Fresh to You stand is located off Route 896 near the University’s

Townsend Hall — across from the historic farmhouse.  Just follow the signs down Farm Lane.  Produce is sold on Fridays from 11 AM to 4 PM.

Fresh produce ready now and young plants at the UD Fresh to You Garden in Newark.

Delaware Goes Native on the Roadsides

My daughter recently sent me a link to a podcast entitled “How Stupid is Our Obsession with Lawns?” You can find it at WYNC Studios Freakanomics.  I was listening to an explanation of how we became obsessed with lawn and why it is not a great idea for the environment, when to my surprise, I heard a man from New Castle, Delaware start to speak.  He described what a shame it is to have miles of mowed roadsides and the missed opportunity for pollinator habitat and other ecosystem services.  He specifically mentioned the I95 rest area in Delaware.

Good news – DelDOT is already in the process of changing the mowed lawn syndrome on Delaware roadsides and is installing two major plantings along I95.  The large mound at the north end of the rest area was planted with clusters of eight native trees, 48 in all.  Small trees were planted because they are more likely to survive the tough roadside conditions.  Once they establish, they will provide shade, flower color and fall color for motorists travelling the I95 corridor.  The mound was also planted with a mix of grasses and forbs attractive to pollinators.

A second planting of over 400 native trees and shrubs was installed last week along southbound I95 between the Route 141 and Route 7 exits.  The first step was to seed a pollinator meadow.  Next, the locations of each plant were marked with a flag or spray-painted “X”.  It took almost one full day to unload and stage the plants close to their planting sites.  Then planting began.  Large shade trees, including scarlet oak, sour gum, sweetgum and red maple were installed.  Grove-forming trees, pawpaw and persimmon, should spread into large native clusters.  Redbuds will bloom with pink flowers in the spring and blackhaw viburnum will have large clusters of white flowers a bit later.  Eastern red cedar and American holly will provide some evergreen cover for the salvage yard on the other side of the right of way.  A wide variety of native shrubs will fill in to provide a complex native landscape.  We reap so many benefits from this type of landscape beyond the obvious fact that is simply looks much more interesting than mowed lawn.  We provide habitat for pollinators and other wildlife.  We allow water to soak into the ground rather than run off into ditches and surface water bodies.  We clean the air, removing pollutants and particulates. In addition, we sequester carbon.

DelDOT has also reduced mowing along Route 1, mowing only a beauty strip on the edges of the medians and mowing just past the ditch line on the roadsides.  Some medians have been seeded with native warm season grasses and others have been allowed to grow with existing vegetation.

Keep an eye on these locations as plantings develop and see how Delaware roadsides can make a difference for the environment!

Plant staging for the I95 southbound planting between Route 141 and Route 7 exits.

Central Park in NYC

Way back in the 70’s I was a student in Plant Science at University of Delaware.  Two of my classmates were Susan D’Innocenzo (now Susan Brutico) and Doug Blonsky.  Susan now teaches plant materials at Longwood and works in visitor services at Chanticleer and Doug is the CEO of the Central Park Conservancy in New York City.  We had a little reunion last week and got a fascinating insiders tour of Central Park.  New Yorkers and visitors love Central Park as a great escape from the bustle of NY City, but it is also a great garden destination.  Over 150 years ago, Frederick Law Olmstead and Calvert Vaux designed this amazing park in the heart of Manhattan.

Doug started working in Central Park in 1985 when it was filled with drug dealers and addicts.  He has seen and been significantly responsible for its current renaissance.  He took us up to the northern end of the park and showed us the recent renovation of The Ravine.  This area had become choked with vegetation, views obliterated and water sat stagnant until Doug’s team of landscape architects, conservancy gardeners and volunteers began the arduous process of clearing out unwanted plants, removing sludge, restabilizing banks and planting many wonderful native plants.  We walked under an arch (The Huddleston Arch) made of massive boulders of Manhattan schist.  Doug told us the story of the day in 1865 when the interior scaffolding was removed and the work crew witnessed
Vaux’s brilliant engineering as the arch stood strong with the stones “huddling” against one another.

It is easy to forget you are in the heart of one of the biggest cities in the world as you listen to the sound of water flowing over stones and birds chirping. Charming woodland paths and rustic bridges lead you to a natural swamp that provides a great stopover for those birds as they rest along one of the major north/south flyways.

The Mall in Central Park is lined with American elms, some old ones that have survived Dutch elm disease and many Dutch elm disease resistant varieties planted more recently.  It is reminiscent of the UD green, without the academic buildings outside the path.  Each elm has asters planted at its base to protect the trunk from sloppy lawn mower operators—a strategy that could be used in many other public landscapes.  Some of the park trees have unmowed grasss at their bases, another good way to protect their trunks without ringing each tree in a circle of mulch.

Wandering the park after we left Doug to the rest of his busy day, Susan and I talked to the gardener of the Dene slope as she worked with volunteers to weed the newly established meadow and make room for a new planting of native bleeding heart (Dicentra eximia).

Earlier in the day (at about 6 AM) I joined hundreds (maybe thousands) of runners, walkers and cyclists all using the park for healthy exercise.  Later, we saw mothers pushing strollers and toddlers scampering on playgrounds equipment as others gathered for a pleasant conversation as their dogs romped in the dog park.  It was a far cry from the scary, drug-ridden park of the not-so-distant past.  Central Park in New York City is definitely worth a visit!

A natural area with banks stabilized by a planted coir log.

Susan and Doug admiring the Huddleston Arch

Plant Invaders – Callery Pears

After an early start, then a bad freeze, this spring has settled into normalcy. In Delaware that means some glorious warm sunny days and some cold, windy, rainy days.  We’ve had an opportunity to enjoy lots of spring flowers that have been long-lasting as the weather stayed cool. One set of flowers I was not excited to see though, were the blooming Callery pears. These early flowering trees have started to clog our roadsides. They are overtaking woodland edges and many unmanaged landscapes. While you may find blooming white trees on the roadside attractive, the sad truth is they are crowding out native trees like serviceberry, dogwood and sassafras that should be blooming along in wood edges and roadsides in the spring.  How did this happen?  Bradford pears, the dominant Callery pear planted ubiquitously in the 80’s and 90’s did not produce fruit, so it didn’t spread into open landscapes.  But, it was replaced with a wide variety of cultivars bred for better branch angles to reduce the problem of splitting limbs, that plagued Bradford pears.  The wide variety of cultivars resulting in cross pollination so now Callery pears are prolific fruit and seed producers.  And that means they are everywhere!

If it bothers you that an invasive exotic species is now the dominant tree on Delaware’s roadsides, there is something you can do—remove the pears at your home and from any landscape you control.  That won’t help with those that have already escaped into unmanaged landscapes, but if everyone removed Callery pears from their property (as well as the other popular landscape plants on the Delaware Invasive Species list – burning bush, Norway maple, Japanese barberry, and privet, to name a few) we could start to make a difference in protecting our natural areas and preserving our native trees, shrubs and perennials.  It is true that what one person does won’t matter, but if everyone removes invasive plants on their property the collective effort will matter.

The good news is when you remove plants, you get to replace them with new species.  You can select native trees and shrubs that will enhance your landscape enjoyment and attract native wildlife to your garden.  For suggestions on what to buy, try consulting a Delaware Certified Nursery Professional (CNP).  The Delaware Nursery and Landscape Association, in conjunction with Delaware Cooperative Extension developed a program to certify professionals in the nursery and landscape industry.  This is a voluntary certification, but it is a good way to ensure you are hiring or buying from a professional.  Delaware CNPs purchase and study a manual and then pass a difficult exam that tests their knowledge of plants, soils, diseases, insects, weeds and many other aspects of landscape management.  If you want to find out whether a business employs CNP’s, consult the DNLA website (http://www.dnlaonline.org/for-professionals/delaware-certifications).

Certified Nursery Professional LogoLook for this logo to identify Certified Nursery Professionals in the nursery and landscape industry.

Crazy Weather May Warrant Plant Replacements

We have had some crazy weather this spring. Warm days in January and February caused cherries and some magnolias to bloom extra early and even some trees to leaf out early.  Trees that leafed out early in most cases had tender leaves burned back when cold temperatures hit.  That should not be a problem for most trees.  Unless the tree is already under serious stress, a tree is capable of sending out a new set of leaves.  Sycamores often have to leaf out twice around here because they are so susceptible to defoliation due to anthracnose (a fungal disease) in a cool, wet spring.

Our warm winter was followed by a March snow storm with heavy rain-laden snow that wreaked a different type of havoc on trees.  Some trees were uprooted and others left leaning.  Once a tree has been uprooted it is usually a “goner.”  Even leaning trees are hard to save.  When ice and snow pull a tree over, the fine roots and root hairs are stripped away.  Root hairs and fine roots are in close contact with the soil, so when larger roots pull away from the soil, which is what happens to cause the leaning, the root hairs are left in the soil and are no longer attached to the roots.  Roots take up water and nutrient through their root hairs.  Plants can regrow root hairs, but if a large part of the root system is damaged, the tree may not be able to take up enough water and nutrients to support the growth of new roots hairs and fine feeder roots, let alone leaf out and grow normally this spring.

If a relatively small tree is leaning slightly, you may be able to use a shovel to right the tree and then stake it temporarily to keep it straight while new roots grow to re-stabilize the tree in the soil.  But, a large leaning tree or a tree that has fallen over completely should probably be removed.

The good news is this gives you the chance to plant something new.  A great opportunity to find new and interesting plants is the University of Delaware Botanic Gardens plant sale.  The sale is held over the weekend of Ag Day every spring.  This year that will be Thursday, April 27, 3-6 PM (UDBG members only; to become a member go to http://ag.udel.edu/udbg/friends/udbgfriends.html), Friday, April 28, 3-6 PM and Saturday, April 29, 9:30 AM – 4 PM (Ag Day).  This year the sale is celebrating 25 years of bringing interesting and hard to find plants to the gardening community. The plant sale catalog is available online (http://ag.udel.edu/udbg/events/documents/2017UDBG__Spring_PlantSaleCatalog.pdf.  If you want to learn about some of the plants at the sale, come to the Spring Plant Sale Preview Lecture on April 5 from 7-9 PM in The Commons in Townsend Hall on UD’s campus.  The lecture is $5 for UDBG Friends and $10 for nonmembers.  On Wednesday, April 12 from 4:30-6:30 PM, Dr. John Frett will lead a guided walk of the 2017 Plant Sale Highlights.  The guided walk is also $5 for UDBG Friends and $10 for nonmembers. Register for either event by emailing botanicgardens@udel.edu or calling 302-831-2531.  Proceeds from the sale support internships for students to work in the gardens and learn about public garden management.

UDBG Plant Sale Catalog cover celebrating 25 years of featured plants!

Harbingers of spring

Little did I know when I planned to write this article, we would have a week with temperatures in the sixties and even reach the seventies for a few days in February.  It does feel as though spring is arriving early this year.  However, leaves are not out yet and you can still walk through the woods and find some of the early harbingers of spring.  One of my favorites is the skunk cabbage (Symplocarpus foetidus). Much maligned for its smelly foliage, inconsequential flowers and leaves that start to melt down in late spring; it has wonderful qualities as well.  When the forest floor is still completely brown with old leaf litter, you can find the unusual flower buds peeking up through the leaves.  Look in wet woods where skunk cabbage is plentiful and you will find four-to six-inch high hood-like leaves that enclose the flowers.  Some leaves are deep wine or red and others have mottling with patches or stripes of yellow or yellow green.  The leaves usually twist and eventually open to reveal a round flower head peering out. The flower is a cluster of petal less flowers with stamens that protrude, giving it an interesting texture.  Skunk cabbage is one of the first flowers available for our pollinator insects.  Bees are already out visiting flowers this spring, and they are finding skunk cabbage pollen to bring back to their hives.

The large, wide leaves emerge after the flowers.  Their chartreuse green color is stunning in the otherwise barren woods.  Skunk cabbage grow in moist conditions and only last a few months.  The leaves start to die back at the end of spring/early summer.  However, their early flowers are a fun find and their colorful leaves brighten up the bleak woods at the end of winter.

Another early spring ephemeral (plant that comes up in spring and dies back to the ground before summer) is Virginia bluebells (Mertensia virginica).  Virginia bluebells have bell-shaped (duh!) blue flowers borne on spiral shaped cymes at the end of arched stems.  Some flowers are pink, especially in bud.  This flower is another bee and butterfly favorite.  Its bright green leaves also brighten the forest floor in early spring.

Bloodroot (Sanguinaria canadensis) is another early bloomer with white flowers that come out before the leaves in early March.  Delicate white petals and yellow stamens are quite showy.  Leaves emerge after the flowers, are a fleshy consistency, and spread out to a wide toothed platter shape. Bees and flies pollinate bloodroot, but ants spread their seeds.

If you are tired of looking down at the forest floor for spring interest, look up.  Red maple is blooming now!  The flowers have very small petals, but the bright red stamens are showy enough that trees look red when viewed from a distance.

We will probably still have some cold weather to endure at the end of winter and beginning of spring, but seeking out the early blossoms and bright, cheerful leaves of these native woodland species can provide some diversion before the weather warms up completely.  Enjoy!

Mottled twisted leaves are covering early flowers and a few bright green leaves are starting to open on this skunk cabbage growing at the edge of a stream.