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     Last week I discussed some of the new breeding in our native plant species, like coreopsis, purple coneflowers, and eupatorium. This week I’d like to share a few more interesting plants, as well as think about how we get new plants and where they come from.

     Longwood Gardens hosted an Independent Plant Breeders Conference a few weeks ago. Who went? University folks, Proven Winner Trial garden managers, public garden horticulturalists, nursery owners who dabble, nursery owners who are serious breeders, scientists from the National Arboretum, employees of commercial breeding companies, patent law attorneys, plant introduction specialists, and a few who fell somewhere in the middle. It turns out there are a lot more plant breeders out there than I thought. Not all breeding is done by big breeding companies. In fact, with perennials, most is not. Bill Radler, the breeder of the famous Knock Out® Rose, a rose lover from the age of 9, made crosses in his back yard, and started the seedlings in his basement. Someone joked, “He started out an independent breeder and ended up independently wealthy”.

     Public gardens and arboreta are also a great source for new plants. The Chicago Botanic Garden has a very well-respected plant evaluation program, and in the early 90s started breeding some of the outstanding varieties of its trials. Out of this work some of the first orange coneflowers appeared. Most recently, they introduced several false indigo hybrids in the Prairieblues™ series. Several species of our native blue, white or yellow Baptisa were crossed to produce beautiful multicolored blooms. Spring blooms are followed by attractive black seed pods which are nice for dried flower arrangements. These plants are drought tolerant and tough as nails once established. New cold hardy crape myrtle selections came out of the National arboretum.

     The Morton Arboretum in Chicago also introduced 15 tree or shrub cultivars, mostly natives. A lot of new hybrids are also discovered or bred by savvy nurserymen. Dan Heims from Terra Nova Nurseries, in addition to being an all-around fun guy, has revolutionalized coral bells, and several other native perennials. Terra Nova has crossed five native species of heuchera to get colors, broadened heat, and cold tolerance and ruffled leaves from the original unassuming coral bells. Some of my favorites are ‘Caramel’ bronzy foliage with pink undersides, ‘Electra’ chartreuse foliage with red veins, ‘Obsidian’ deep velvety purple and ‘Miracle’ burgundy leaves with curled lime edges. Another group of native plants I’m excited about are phlox. There are low-growing spring flowering phlox for the shade or sun, and four species of summer flowering tall phlox, all of which are native. The spring flowering ones are relatively trouble-free and look great mixed with spring bulbs or foam flowers. This is a winning combination found at Longwood’s Pierces Woods.

The summer flowering phlox have always been a staple of the garden because they are fragrant, attract butterflies, make nice cut flowers and provide color for the summer perennial border. Their biggest drawback has been powdery mildew. Many of the new hybrids have addressed this issue by crossing with another species to give mildew resistance, or looking for seedlings that are especially tolerant to mildew. Some of my favorites in this category are ‘Minnie Pearl’ a great white hybrid, ‘David’s Lavender’ a mildew resistant lavender flower, and ‘Flower Power’ a beautiful new blue.

      Native plants are great in the landscape because they support the local wildlife, and are well adapted to our conditions. With the attention given to improving their flaws thanks to our public gardens, nurserymen, and private breeders, they are more garden ready than ever.

     Fall’s cooler temps are here to stay, and with Thanksgiving right around the corner the gardening season is about on its last legs.

     As we plan for spring I’m excited to see all the new plant breeding work being done with our local natives. If you asked 5 different people what a native plant was, I’m sure you’d get 5 different answers, but here is my non-purist one:

       "Any plant whose parentage was found in this area before European settlers appeared"

     There are lots of reasons why using native plants in your landscape is a good idea. They provide food in the form of pollen, fruit, seeds, etc for our local wildlife, they should be better adapted to our soils, and resistant to local diseases. Most of the new selections or hybrids still accomplish these goals, while being more attractive in the garden.

     Some of the most popular groups of native plants breeders are focusing on are echinaceas (purple coneflowers), Baptisia, coreopsis, heuchera (coral bells), and eupatorium (Joe Pye Weed). Echinacea hybrids have been getting a lot of press lately; the plain old purple coneflower certainly isn’t plain anymore, let alone purple. By crossing a yellow species found in the southern US, Echinacea paradoxa with our common Echinacea purpurea we now have reds, oranges and corals, never before seen in coneflowers. If you’ve read any gardening magazine in the last 2 years, I’m sure you’ve heard of ‘Mac N Cheese’ or ‘Tomato Soup’.

    ‘Tiki Torch’ is a great orange from that same family, and my new favorite,‘Coral Reef’, is a beautiful double salmon-colored flower. I could find over 100 new named cultivars of echinaceas without looking very hard. These hybrids may not all produce pollen, or seeds to benefit our local wildlife, but they certainly are an interesting addition to the perennial palette. If you’re worried about butterflies and goldfinches, stick to the purple ones, where flower size, stem strength, and plant shape have been improved without affecting pollen or seed-making.

     Coreopsis is another great group of plants where the breeders have been busy. From our native yellow threadleaf type we now have beautiful cultivars with red eyes, and improved compact habit. Flower sizes have gotten larger, bloom time is longer and disease resistance has been beefed up. One of my favorites, ‘Route 66’ has a reddish eye and boomed in my garden from June until the end of September.

     One of the biggest problems with these new hybrids is hardiness. Some plants while getting larger, more beautiful flowers lost the ability to survive the winter. ‘Snowberry’ Coreopsis is one such plant. Trying these new cultivars says a lot about who you are as a gardener.

     Do you like to take a risk and try the new, interesting things? Or are you willing to wait a few years until the best are established and the dogs are eliminated from the field?

     One of my favorite gardening stories is about Allen Bush, a great plantsman from North Carolina who runs the North American branch of the German seed company Jelitto. He was in Europe for a meeting and kept seeing this wonderful, tall, purple flower covered with butterflies, in public gardens, and collegues yards. He decided to order 1000 seeds to bring it back and trial in the US. When he got home, he was a little chagrined to find Joe Pye weed growing wild in his back meadow. Eupatorium grows up to 6-8 feet tall, but some of the new selections like ‘Baby Joe’ or ‘Little Joe’ are a more manageable 2-4 feet. They tolerate wet soils, bloom in the late summer, and the large purple flower clusters attract butterflies.

     I’m running out of room, and I’m not done yet so I’ll pick this up again next week.

     Wow, this year is quickly disappearing. Several weeks ago our Thanksgiving cactus climbed the basement stairs and perched briefly on the television cabinet. It didn’t take long before it was banished to its underworld haunts and replaced by the first hints of Christmas.
      The cactus has done this for more years than I can remember. No one any longer tries to count the number of flowers. Even a bushel basket would no longer hold it. If you’re into that plant or its Christmas or Easter sisters, I think the key to success is neglect.
      A nine-month-old grandson assisted in getting a Christmas tree. He was sitting on the living room floor occupying my wife so I got dispatched alone to a nearby tree farm to make the big purchase. I chatted with the owner for a number of minutes to disguise my speed in selecting a tree.
      As usual, I glanced at the white pines, thought about hiking to the top of the hill to look at the concolor firs and quickly selected a well pruned Douglas fir in a size that left me win the wrestling match. If you visit a cut-your-own farm in this area you will find mostly Douglas firs.
       Once home, it quickly found the tree stand, found its spot in the living room and received a drink of warm water. All that happened in easily less than an hour from the field to a blank slate ready for ornaments. If you buy a precut tree, cut a sliver off the trunk to open its water channels and don’t forget the warmer water for its first drink.
      The yard is still very green and I have been planning a second attack on fallen leaves but it’s been nasty cold. I also hope to find a few hours, no days, to complete a bit of mulching that is an ongoing project when (if) I get to it.
      One suggestion to anyone who did any late October or early November planting. Now that the ground is starting to freeze, scatter a light coat of mulch around the new transplants. I doubt if the new plants have had much time to root in and a bit of mulch on the frozen ground will keep the soil temperature more uniform and prevent heaving.
      At the greenhouse, seeding starts in January, transplanting in February, so my thoughts are turning to Christmas and plans to seek warmer temperatures, even if it takes several days of driving to find them. It’s about time to start counting the number of days until spring.
      I’d guess that bird watching, my other hobby will bring a few winter entries. Otherwise, look for more scribbling from Kris or I in the spring. Have a wonderful holiday season. We all have lots to be thankful for.

     When the grandkids show up with red hands and large red circles around their mouths I know that it is strawberry season. They like them and I like them because they are an easy addition to the garden.
      Plant them in early spring. The experts tell you to remove all the flowers the first season. Here impatience usually prevails, and I just get most of them and eat a few berries, too. Each plant will shoot runners producing new plants. Drag the runners into rows rather than let them form a bed. Get ready to enjoy lots of berries in year two.
      Once established, fertilizer them lightly after harvest, but never in the spring. Spring fertilizer produces great leaves but your goal is great berries. After harvest I mow the tops off with the lawnmower set at its highest setting. At that time I use the rototiller to narrow the rows.
      My goal is to keep the row width to one foot. That provides air circulation which eliminates the need for fungicides most seasons. Unless you are immediately beside a woods, insect control is also seldom a problem.
      My plan is to let the rototiller slowly let the strawberry rows walk across the garden. That strategy will yield a succession of young plants without the need to replant.
      I finally managed to follow all of the above instructions and this year expect to see lots of reddish grandkids and a great store of strawberry jam waiting for me in the pantry. I confess that over the last forty plus years I have eaten so many strawberries that now my body will tolerate only one or two handfuls a day.
      Blueberries are also a potentially chemical free fruit for the garden. There are three hurdles between you and growing blueberries. Expect a reasonable crop by the third season if you can make them happy.
      First, you need to reduce soil ph to 5.0 or under. That means a big effort to drive it down. My suggestion is to get a soil test and follow the instructions. I use sulfur and acid mulches, but the experts may direct you to aluminum sulfate, which most likely is faster.
      Pruning is easy with this multi-stemmed plant. Cultivate five or six stems. Once established, cut out the worst old stem and keep the best new stem. Doing more usually is counterproductive.
      Third, plant enough to share with the birds or figure out how to shield the ripening fruit from the birds.
      Grapes seldom will escape black rot without some fungicides. They grow quickly and will start producing in year two or three. Fertilize lightly each spring. The vines will need to be supported. Pruning is important.
      Expect each vine to produce no more that 50 clusters and prune accordingly. There is a fruit bud at each leaf. A properly pruned grapevine will look like a skeleton. Be brave, do it and you will be rewarded.
      As I noted some months ago, I planted raspberries this spring. Remaining on my bucket list is a number of the uncommon fruits. Maybe I can eventually paint hands and mouths a color other than red. Stay tuned.

***Blueberry pruning diagram courtesy of University of Georgia.

     There is an oft repeated claim that every time a honeybee or other pollinating insect successfully visits an apple flower it produces another seed in the future fruit. The claim continues that the more seeds, the larger and better shaped the fruit becomes.
      I don’t know if that is true, but I have heard it often enough that I almost believe it. In any case, pollination is important with our tree fruits that have multiple seeds. Of course, these are apples and pears.
      With pears you need two different varieties. The same is true with apples, except a few varieties produce pollen that is generally ineffective in the pollination game.
      You certainly have noticed that the stone fruits, like cherries or peaches, produce single blooms while apple and pears produce clusters of blooms. The center, or king, bud blooms first and will produce the best fruit. If the king bud is successful, the side flowers generally fail. On the other hand, if the king bud fails, there are backups to produce fruit.
  Culturally, pears are rather slow growing and have a tendency to produce a rather narrow, upright tree. Training to get the branches to spread is desirable. Insect wise, there is a summer leaf chewing insect that excretes a sugary substance that will discolor the pear’s skin. I also have noticed that yellow jackets or other sting bees like ripening pears.
      Pears are generally picked rather green. Placing in a plastic bag is the best ripening and storage hint I know. Try it, even with store bought pears.
      Your first consideration with apples is the size of the tree, which is determined by the vigor of the root. The smallest will need a stake for support, while the standards often are quite large. I favor the semi-dwarfs. One catch is that each apple variety has its own growth habit and final size. In other words, two different varieties on the same rootstock may vary substantially in size and shape.
       Damage from apple scab, a fungus, will range from thick, dark blotches on the skin to cracked and misshapened fruit. Without control, you can’t grow useable apples. Recently there have been varieties introduced that show some resistance to scab. I have no experience with these. There are other disease and insect problems to think about, but they are dwarfed by the scab problem.
      The day before I wrote this, there was an article in the Wall Street Journal talking about efforts to save some claimed 3000 varieties of heirloom apples. I could question the 3000 number, but I won’t. In general, heirlooms can be fun, tasty, ugly and more of a challenge to grow.
      To me, apples and pears are a bit harder to grow successfully than peaches, but still well within the reach of the avid home gardener.

***Apple scab photos courtesy of Cornell University