Support National Pollinator Week: Plant Trees for Pollinators

sweet bay magnolia blooms in summer

It is amazing that something as small as a bee is vitally important to our food supply. As pollinators, bees transfer pollen thus ensuring that plants and crops develop fruit and seeds for us to consume. But bees are not the only keystone species that we depend on, we also need other pollinators such as butterflies, moths, beetles, flies, and birds, including hummingbirds. About 80 percent of the world’s flowering plants depend on pollinators (the others are wind pollinated). According to Cornell University, pollinators are responsible for every third bite of food we eat.

Unfortunately, pollinator populations have declined due to pesticides, habitat loss, and disease. Gardeners who are aware of this problem have deliberately planted flowering perennials and annuals to provide pollen (protein) and nectar (carbs). Because of their dramatic 90 percent decline in population over the past 20 years, monarch butterflies have received quite a lot of support. Many gardeners are planting milkweed – the one and only plant for monarchs — or trying to produce more butterflies with home kits. Bees too have received national attention. Nurseries promote bee friendly flowers and gardeners have planted bee magnets such as Joe-pye weed (Eupatorium), goldenrod (Solidago), and gayfeather (Liatris).

persimmon fruit, thanks to pollinators

Plant Trees to Support Pollinators

These efforts have helped the pollinators and certainly gardeners have come to appreciate the importance of pollinators. However, an overlooked source of food and protection for pollinators are trees. Trees provide more flowers, plenty of foliage for larva (caterpillars), and a large infrastructure to hold hives and nests. Because of the number of flowers a canopy provides, trees can provide more pollen and nectar compared to annuals and perennials. Plus, as homeowners move from house to house, the herbaceous landscape may change but usually the trees and all of their tiny inhabitants remain.

Plant Small Native Trees for Homes

“Trees are a permanent fixture,” said Steve Nagy, an International Society of Arboriculture (ISA) Board-Certified Master Arborist and Assistant District Manager of The Care of Trees. The Care of Trees is a division of the Davey Tree Expert Company, founded in 1880. Based in Ohio, the Davey Tree Expert Company has offices across North America–Steve is based in a northern Virginia office.

For attracting pollinators in the Washington DC metro area, Steve recommends native trees that thrive in our particular climate (cold winters and hot, humid summers). “We recommend native trees because the chances of them growing well is higher that non-natives,” he explained. For typical suburban lots where space is a premium, Steve recommends swamp white oak (Quercis bicolor), willow oak (Quercis phellos), post oak (Quercis stellata), cucumber magnolia (Magnolia acuminata), sweet bay magnolia (Magnolia virginiana), black gum (Nyssa sylvatica), little leaf linden (Tilia cordata), persimmon (Diospyros virginiana), and serviceberry (Amelanchier).

“Sourwood (Oxydendrum arboreum) is a great tree, too,” said Steve, “It is a typically overlooked native with good fall color.”

Plant Trees that Flower at Various Times

heavy with summer-blooming flowers, the crape myrtle branches bend down

While a tree can provide many flowers, usually it only flowers for a few weeks. Because different pollinators are active at various times of the year, Steve recommends planting trees with various bloom times. Instead of planting the well-known spring bloomers such as flowering cherry trees, flowering plums, star magnolias, saucer magnolias, and redbuds, homeowners can plant summer blooming trees such as little leaf linden (see video below for bees pollinating a linden tree), persimmon, cucumber magnolia, southern magnolia (Magnolia grandiflora), and crape myrtle (Lagerstroemia).

Plant Trees that Support Specific Pollinators

Another reason to plant trees is that certain pollinators require specific tree species or genera. Similar to the monarch butterfly’s relationship with milkweed, the spicebush swallowtail caterpillar only feeds on spicebush (Lindera benzoin) and sassafras (Sassafras albidum). The zebra swallowtail caterpillar only feeds on young paw paw leaves (Asimina spp.) and the pink-striped oak worm moth gets its name from its preference for oaks (Quercus spp.).

paw paw trees are vital to the zebra swallowtail

Plant Trees in the Fall

This week is National Pollinator Week. Now is the best time to learn more about pollinators and to identify new trees to plant to support them. However, summer is not the best time to actually plant trees. Because trees take longer to become established than perennials and annuals (larger plant hence more root structure and more foliage), Steve said the best time to plant trees is in the fall. “If you can get planting done by Mother’s Day,” said Steve, “the tree has a chance to make it through the hot summer but fall is the best time.” Steve also recommends to plant smaller rather than bigger but one can plant bigger plants in the fall. Fall, as opposed to spring or summer, offers warm soil but cooler temperatures, thus the amount of transpiration or water loss is less. The tree can devote energy into root establishment, not making up for water loss due to heat.

For information on how to plant a tree correctly, the Davey website has an extensive collection of articles and videos on tree planting and maintenance. If you need more personalized assistance, Steve mentioned that homeowners can request a free consultation by calling or completing a form on the website. A certified arborist can come to one’s home to evaluate the trees and landscape and devise a strategy to meet the goals for that specific property.

This week, celebrate National Pollinator Week by learning more about pollinators, identifying the best plants and trees for pollinators in your area, and incorporating best practices to protect, harbor, and feed pollinators.

 

This Week is National Pollinator Week: Learn How to Support Vital Pollinators

This week, June 18 to 24, 2018, is National Pollinator Week. Organizations across the country will host pollinator awareness events.  In Washington DC there are several events this week. Also, you can participate in the Million Pollinator Garden Challenge by making your garden pollinator friendly and registering your garden at the site (free). I just registered my Virginia garden, a typical suburban home, for the Million Pollinator Garden Challenge.

For National Pollinator Week in 2016, I featured an herb a day that attracts pollinators. Marjoram, cilantro, dill, sage, chives, basil and thyme are common culinary herbs that when left to flower will attract bees and butterflies. Day seven, marjoram, provides links to the herbs as well as other pollinator related resources and organizations.

This year I am focusing on a different group of plants that attract pollinators, see my article tomorrow on pegplant.com.

Happy Father’s Day! Enjoy a Bouquet of Summer Blooming Bulbs

Happy Father’s Day! In April I wrote an article about creating a container of summer blooming bulbs. Today, the container is in full glory. Earlier in the spring, most of the oxalis bloomed although you can see one lavender blossom on the left. The remaining burgundy foliage complements the color of the lilies. There is one dahlia on the right, this is actually the second one that has bloomed so far. The lilies are large and fragrant and there are several buds too. Looking forward to enjoying this all summer long.

Register to Learn How to Grow and Use 13 Culinary Herbs

On Saturday, June 23, from 10:00 am to 11:30 am, I will teach a class on culinary herbs at Green Spring Gardens. I will discuss 13 herbs, the cultural requirements, culinary uses, and harvesting and preserving methods. This is not a Powerpoint presentation. I will bring the actual plants so you can touch, taste, and smell!  Everyone will receive a handout with herb information and local resources. And, if you know me, you know there will be a giveaway. Someone will go home with an herb plant. Register online for the “Plants and Design: Herbs–A Baker’s Dozen” class at www.fairfaxcounty.gov/parks/parktakes using code 290-387-4801 or call (703) 642-5173. See you on Saturday, June 23.

Native, Deer-resistant, Summer-flowering: What More Can You Want in a Shrub?

A single blossom on a young Calycanthus ‘Aphrodite” in my Virginia garden

I have been admiring Carolina allspice (Calycanthus floridus) in other people’s gardens for a few years, taking photos whenever I can. This is such a beautiful plant I don’t know why other people don’t grow it more often. A native, deciduous shrub, Carolina allspice grows to 5 to 8 feet tall, is deer resistant, and has no major pests/diseases. The leaves are green and large for a small bush and the brown red flowers bloom all summer long.  Pollinated by beetles, the 2-inch flowers look like a cross between a star magnolia (outer strap-shaped petals) and a lotus (curved inner petals with a central, raised button). In the fall, the leaves turn golden yellow.

Calycanthus ‘Aphrodite’ at High Glen Gardens looks like a cross between a star magnolia and a lotus blossom

Fortunately Spring Meadow Nursery read my mind and sent me the cultivar Aphrodite two years ago as part of their Proven Winners ColorChoice collection. Aphrodite’s flowers are redder than the species and are supposed to smell like apples. In my Virginia garden, my 3-foot tall youngster is thriving under the edge of a red maple’s canopy, so it receives partial sun. This past week, Aphrodite bloomed for the first time.

I cut the flower and put it in a vase. There was no scent but I have read that young plants do not always have a fragrance. Apparently this attribute comes with maturity. I did crush a leaf though and the camphor scent was nice, almost lemony. It reminded me of a friend who would put eucalyptus branches in her car so the heat would release a pleasant scent. The bark too was aromatic when I scratched it.  Mark Catesby said the bark was as “odoriferous as cinnamon” although I think the scent is more like a cross between lemon and camphor. When my plant matures and I get more flowers I will use them for flower arrangements. In addition to the flowers, I could use the leaves and branches for potpourris. But I think I will pass on the car trick, it may create a strong odor, more like a disinfectant.

Regardless of its scent, Carolina allspice is a great shrub for the Washington DC metro area. Aphrodite certainly holds great promise in my garden.

Mature shrubs of Calycanthus ‘Aphrodite” at High Glen Gardens, Frederick, MD

Public Gardens and Demonstration Gardens in the Washington DC Metro Area

I have updated my list of public gardens and demonstration gardens in the Washington DC metro area, see tab with same name on my website, pegplant.com. Many of these places are perfect to take the kids and visiting friends and family to this summer.

Public gardens are living examples of which plant performs well in the area. Many public gardens have a reference library, gift shop, web site, and gardening hotline. Usually, public gardens host seminars, workshops, classes, events, and plant sales. They may publish their own books on plants for the area or distribute free handouts. Some have staff horticulturists who can identify plants or answer questions.

Demonstration gardens are a great way to learn what works in our area and how to manage our local issues, such as deer. The gardens are open to the public, every day, from dawn to dusk, free. Each county that has a Master Gardener program usually has at least one demonstration garden, managed by the volunteer Master Gardeners.

If you have suggestions for additions, feel free to send them to me by commenting on this post.

Basil: More Than Just Pesto

Pesto Perpetuo basil

I cannot imagine a summer without basil; it is the essence of summer. But I don’t limit myself to just one — there is a family of basils in my garden. I grow lemon, lime, sweet, Thai, holy, and cinnamon, just to name a few. It seems that most people only know sweet basil and only one use: pesto.  Granted sweet basil has become the poster child for this plant, but there are many different types to explore.  The genus Ocimum has more than 30 species. Within the Ocimum basilicum, there are more than 40 cultivars.  All of these can be used in a variety of ways both in the garden and home.

Basil is an annual, herbaceous plant that prefers warmth, full sun, and well-drained soil. If I think of basil as an annual plant that also flowers, I can imagine how to use the different varieties. Also, classifying basil into five basic categories makes it easier to select a particular type for a particular function.

  • sweet green foliage (the green plant we always associate with pesto such as Genovese or Italian large leaf)
  • small leaves and dwarf size (spicy globe basil, dwarf Greek basil, Minette, or Pluto)
  • colored foliage (purple leaved Purple Ruffles or Dark Opal or light green/cream variegated Pesto Perpetuo)
  • colorful flower heads (Thai Siam Queen has purple stems and fragrant purple flowers), African blue (many prominent purple flowers), or cardinal (purple stems, purple/red flower heads)
  • fragrant leaves (holy, lemon, or lime).

Some basils overlap into more than one group. For example, cinnamon basil has fragrant leaves, purple stems and veins, and deep pink flowers. This plant provides scent and flavor as well as color.

cinnamon basil

The following are suggestions for using basil. The exact species or cultivar depends on your personal preference and availability in your area.

Basil as a Container Plant

All types of basil can be used as container plants either for green, variegated, or purple foliage, or colorful flower heads. Basil comes in different sizes from 8 inches to 4 feet so make sure the maximum height is in proportion to the container. Companion plants must also like well-drained soil and the container should have drainage holes. I had a few extra holy basil plants that I stuck in the same container as my bush beans and both are thriving.

basil flowering in container with ornamental pepper

Basil as an Annual in the Garden

All types can be used as an annual in the garden bed, either for green, variegated, or purple foliage or for colorful flower heads or simply to fill in a gap. If you think of basil as a flowering annual like a marigold, you could plant them in the same type of location. My Thai, lemon, and lime basil have filled the gap left by my bleeding heart plant, which goes dormant in the beginning of the summer. In particular, the dwarf basils are best for creating a tight edging effect. They have small leaves, similar to boxwood, and are great for delineating a garden bed in the summer. Spicy globe basil is often used to outline a garden bed.

purple basil

Basil as a Cut Flower in a Vase

The basils that are grown for colorful flower heads or dark foliage are beautiful in flower arrangements. For example, Thai and African blue provide purple flowers and Purple Ruffles provide purple leaves.

African blue basil

Basil in Potpourri and Dried Flower Arrangements

Basil produces a tall, sturdy flower stalk that dries well and can be used in dried flower arrangements. The leaves or flowers can be used in potpourris, especially the more fragrant leaves such as cinnamon basil. When I cut Thai basil and fresh flowers such as dahlias for a vase, I can throw away the dahlias after they have past their prime and put the Thai basil flower spikes in another vase with purple gomphrena as a dried flower arrangement. A basil flower has a rigid calyx, like a socket, that holds the small delicate flower like a lightbulb. Once the flower is past its prime, it drops out and the rigid calyx remains.

Thai basil

Basil as a Pollinator Magnet

Basil’s small flowers are attractive to beneficial insects and bees. Birds, such as goldfinches, love the seed heads. I grow lemon basil in a container on the deck to attract the finches so I can see the birds up close through my kitchen window.

Basil in the Kitchen

Usually a sweet basil such as Genovese is used in pasta, eggs, pesto, soups, salad, and vegetables, but you can try any type of basil.  I use lemon basil with fish and Thai basil with stir fried chicken and vegetables. Thai basil is often used in Asian cuisine because it keeps its flavor at high temperatures.  Holy basil often is used in Indian cuisine and the sweet basil is often used in the Italian cuisine. There are so many cuisines that employ basil and so many recipes it is best to obtain an herbal cookbook.

sweet basil

The purple basils work well in vinegar or oil for color and scented basils such as cinnamon can be used for flavor in either a vinegar, oil, or marinade. I use the cinnamon which has a purple tinge in homemade vinegar and give it as a gift to my family.

Sweet basil is good for butter and the spicy types are good for honey and jellies. I let a stick of butter sit at room temperature for a few hours and then swirl small pieces of sweet basil into it for use on breads and rolls. (This also makes a good gift).

Lemonade, cocktails, tea, and fruit juice pair well with basil. Try adding the spicy, cinnamon, lemon or lime flavored basils to these drinks for flavor or just make a cup of tea with basil leaves.

Basil flavors cookies, pound cakes, and breads (rolls, muffins, flatbreads). I use the sweet basil for flatbreads and dinner rolls and the lemon, lime, or cinnamon for pound cakes. For a real conversation piece, sometimes I decorate a cake with basil flowers, which are edible. The actual flower is small and within the calyx so I have to pull the flower out from the calyx with tweezers. This takes time but is good for a special occasion when you want to “wow” folks.

Basil can be used in sugar syrups for fruit salads, desserts, and drinks. This is especially good with cinnamon, lemon, or lime basil. Make a sugar syrup by bringing to boil one cup of water and one cup of sugar with one cup of leaves and then simmer for 15 minutes. Drain through a colander to remove the leaves and let the syrup cool before using. Keep the syrup in a jar in the refrigerator to have on hand (throw out after a week or two).

glass jar of basil sugar syrup

Another way to “wow” family and friends is to sprinkle strips or ribbons of lemon, lime, or cinnamon basil leaves on fruit salads and/or add the small flowers to the fruit salads (again pull the actual flower out with tweezers).  As mentioned before, coat fruit salads with the sugar syrups or intersperse a leaf with chunks of fruit on a kebab.

Try growing several basils in your garden this summer. They are easy to find at the local nurseries or visit two local herb nurseries: Debaggio’s Herb Farm and Nursery and Willow Oak Flower & Herb Farm.

Pegplant’s Herb Class: Learn How to Grow and Use 13 Culinary Herbs

On Saturday, June 23, from 10:00 am to 11:30 am, I will teach a class on culinary herbs at Green Spring Gardens. I will discuss 13 herbs, the cultural requirements, culinary uses, and harvesting and preserving methods. This is not a Powerpoint presentation. I will bring the actual plants so you can touch, taste, and smell!  Everyone will receive a handout with herb information and local resources. And, if you know me, you know there will be a giveaway. Someone will go home with an herb plant. Register online for the “Plants and Design: Herbs–A Baker’s Dozen” class at www.fairfaxcounty.gov/parks/parktakes using code 290-387-4801 or call (703) 642-5173. See you on Saturday, June 23.

Slugs: Because You Know They’re Coming

mature slug

This week gardeners are complaining about too much rain; next week gardeners will be complaining about slugs. Slugs are related to shellfish and love moisture. They have been doing their happy dance since these rains have started.

Although I rarely see them because they are active at night, I know I have slugs in my Virginia garden. I see the chewed and tattered leaves and the glistening, slimy trails. Slugs particularly love the tender foliage on my transplants – the ones I patiently grow from seed under lights. To prevent them from destroying months of work, I quickly respond when I see any evidence of their existence.

If I see chewed leaves, I sprinkle the plants with Sluggo, a brand name for iron phosphate. This is not a plug for Sluggo, it is a plug for not messing around with homemade remedies – just get the iron phosphate. There are several products with iron phosphate, read the active ingredient on the label. I have found that Sluggo’s cylindrical container with the small holes for sprinkling to be very easy to use. Also, it is safe for dogs and cats, and there are a few stray cats in the area. If for some reason I have run out of Sluggo, I sprinkle crushed egg shells or coffee grounds and then run to the nursery.

I have tried the beer trick. Slugs are attracted to yeast so beer in a lid or saucer, sunken to the ground, is supposed to attract them. Once they fall in they get too tipsy to get out. I have never found them in my saucers and I was never able to reconcile the cost or waste of perfectly good beer on slugs.

Slugs also are attracted to citrus. I have not tried this before but some gardeners swear by putting grapefruit halves on the ground, cut side down, with a pebble on one side (so they can slime in). In the morning, they either lift the citrus and kill the slugs or throw the whole thing in a bag. Another method is to place a clay pot upside down with a pebble and turn the pot over in the morning to pick up the slugs and destroy them.

This is all well and good but when you are working mom, you would rather grab a canister of Sluggo and sprinkle before you run off to work.

slug damaged hollyhock transplant

Another deterrent is diatomaceous earth, it is just not as easy to find as Sluggo or easy to apply. It is a fine white powder with microscopic sharp edges that irritate if not outright slice the slugs. I am always afraid I will breathe in the talc like powder or spill it on my suit as I inspect the morning damage before I run off to work.

And then there is the copper barrier that would be effective if you just had one container or a raised bed. Apparently it causes a type of electric shock to slugs but is not harmful to humans or pets. The only downside is that it is impossible to surround all of your plants in your suburban yard – it is just not practical.

So go to the nursery now before slug season starts. Find a product with iron phosphate and find an easy, quick way to apply it. The easier it is for you the more likely you will be able to fight the slug invasion.

 

June Pegplant’s Post Giveaway: Shrub Rose ‘Sunrosa’ Courtesy of Gardener’s Confidence

Thank you Gardener’s Confidence for sponsoring the June Pegplant’s Post giveaway. Pegplant’s Post is a free monthly newsletter for gardeners in the Washington DC metro area, featuring local gardening events, books, a giveaway, and articles, tips, and advice. With the June issue, one lucky subscriber will win Sunrosa, a fragrant, pink flowering, dwarf shrub rose. Disease-resistant, this 2-feet bush blooms all summer long.