Hosta, Hosta, Hosta

by Tony Avent, Plant Delights Nursery, Inc.

IN THE BEGINNING: My early recollection was growing up in the mid 1960's with hostas in our garden. It didn't seem to matter how many times I road my bicycle thru those clumps along the driveway, they kept coming back...indeed they proved tougher than was I. Little did I know that the plants that I tried to destroy as a kid would become my lifelong addiction. Finally in the fall of 1997, I was able to bring my addiction full circle by spending a month trekking around Korea, observing hosta in their native habitat.
Some folks have grown hostas for years and there is always someone out there that has grown both hostas...the green and the variegated one. I too had this naive attitude until at the ripe old age of 9, my folks took me to visit the garden of Raleigh's Jim Cooper. This person was really strange I thought, as he had over 50 different hostas, which in 1966 was a lot. Of course, at age 9, a place to run and jump was much more important than 50 hostas, but I still couldn't get them out of my mind.
Each successive trip to Cooper's garden found me spending more time with notepad in hand, slowly walking around the hostas beds trying to memorize all of the hosta names (already mastered the states and their capitols). Being a generous sort, and the unofficial ambassador or hosta, Jim Cooper was always free with a division of anything that struck my fancy, although I was aghast when he told me that some hostas costs as much as $100 per plant. Should I call the mental hospital I secretly wondered, or are there more of these people that would spend an entire car payment on one plant?
HOSTA EVOLUTION...CULTIVARS AND SPECIES:
My first hosta was the common variegated one, H. 'Undulata'. Other than the fact that it's as tough as nails, I don't know why anyone would ever buy another hosta after growing this dog. It is tough, divides easily, grows fast, but it sure is ugly! Okay, in spring, it looks great as it emerges from its winter sleep, but it picks up ugly again pretty quick. Even the flowers are so ugly, that I was taught from an early age to run and cut the flowers as soon as I saw the bloom stalks forming. I figured it must be sort of like looking at the Medusa head and if I saw a hosta flower, I would turn into something horrible...like a kudzu vine.
There was several different H. 'Undulata' type hostas on the market, and being a collector wanna be, I searched for them all. There was an all green one called H. 'Undulata Erromena'...the "undulata mistake". Then came H. 'Undulata Variegata' and H. 'Undulata 'Univittata', and H. 'Undulata White Ray', all of which proved to be the same when grown under the same conditions. Only H. 'Undulata Albomarginata' turned out to be worth growing, as the rest were discarded after a few years. I quickly realized that these "collectors" collected plant names, and were not often interested in good garden plants.
I next moved into the H. 'Fortunei' group of hostas, from which many of our truly good garden plants have been derived. They included the wonderful old favorite H. 'Francee'. Not only was it easy to grow and carefree, but the color didn't fade as with H. 'Undulata'. I later would find dozens of good nurseryman that had perpetuated the myth that hostas hated fertilizer, and it made them turn green. I would explain to each of them that H. 'Undulata' naturally turns green (a process called viridescence), and the fertilizer only hastened the process. This was certainly not true of the better cultivar and was only one of the many garden myths that abound.
Another of my early accessions was the Hosta 'Fortunei' selection, H. 'Gold Standard'. I love this hosta that has withstood the test of time as one of the classics. H. 'Gold Standard' can appear as three different plants depending on the light conditions. In bright light it will be nearly white with a green edge. In morning sun, it will be bright gold with a green edge, and in deep shade, it will be chartreuse to light green with a darker green edge. The "fortunei" group continues to yield many of our best garden varieties including H. 'Antioch' (wide white edge on a green leaf, H. 'Striptease' (dark green leaf with a wide creamy center), and H. 'Night Before Christmas' (large green leaf with a wide pure white edge, and H. 'Fortunei Aureomarginata' (dark green with a wide gold edge), and H. 'Patriot' (a H. 'Francee' sport (probably tetraploid) with a wider white edge)..
I had also become acquainted with the selections and hybrids of H. sieboldiana, a species from Japan. However, it was not until I began to travel that I realized the true beauty of this group. It is the gardeners in the cooler climates that do a masterful job with this group along with the closely allied H. 'Tokudama' group. These massive clumps of corrugated blue foliage were the plants that we all dreamed about in the south. It wasn't that we couldn't grow them, they just didn't have quite the "uumph" that they did in the north. Oh, part of it had to do with the fact that the blue on a hosta leaf is wax, and you can guess what happens to wax in 100 degree temperatures with humidity to match. Otherwise, these hostas just preferred cooler temperatures...just like the folks that grew them.
Some of the best garden plants come from Hosta nakaiana. The late Bob Savory of Edina, Minnesota mutated some H. nakaiana seedlings and the result was one of the greatest hostas ever hybridized, H. 'Golden Tiara'. The instability of the genes of H. 'Golden Tiara' has produced many other plants with the same vigorous growth habit and great flowering traits as the parent. They include H. 'Grand Tiara' (wide gold margins surrounding a green center and probably a tetraploid), H. 'Diamond Tiara' (white edges on green leaves), H. 'Emerald Tiara' (green margins and a yellow center), H. 'Golden Sceptre' (all gold), and a number of others.
ODE DE HOSTAS...FRAGRANT FLOWERS:
Of course, to the envy of our northern neighbors, we could do a superb job growing the fragrant hostas. The parent of these fragrant blooming hostas was one of only two Chinese species, the heat loving H. plantaginea. The common name of August Lily had been given by old gardeners, as the clump of shiny green leaves exploded in August with 10" long pure white flowers with an overpowering fragrance usually encountered only when sister spends too long testing samples at the perfume counter.
It was from this lone species that all of the wonderful fragrant hostas that we know today originated. Both H. 'Honeybells' (Cummings) and H. 'Royal Standard (Wayside Gardens) have long been mainstays of the garden...especially in the south. Things changed in the 1980's however as Mississippi's Dr. Kevin Vaughn, NC's Van Sellers, and NY's Paul Aden brought the world of fragrant hostas to the forefront with their introductions including the Iron Gate Series (Sellers), H. 'Summer Fragrance' (Vaughn)- the largest and most vigorous of the fragrant hostas, H. 'So Sweet' (Aden) - vigorously growing round leaves with a wide creamy border and fragrant light lavender flowers, H. 'Invincible '(Aden) with thick glossy green leaves and large fragrant purple flowers, and H. 'Fragrant Bouquet'(Aden) with smooth golden leaves with a creamy edge and large fragrant flowers.
Since these were introduced in the 1980's the floodgates have seemingly burst open. Recent introductions include three sports of H. 'Fragrant Bouquet' found by NC's Bob Solberg...H. 'Guacamole' (chartreuse w/dark green edge), H. 'Fried Bananas' (gold), and H. 'Fried Green Tomatoes' (green). All plants have flowers identical to the parents.
The are also a number of hostas on the market with genes from the fragrant H. plantaginea that share some the characteristics of the parent, but lack the fragrance in their flowers. These include H. 'Fragrant Blue' (Aden),. H. 'Fragrant Gold' (Aden), and H. 'Sum and Substance' (Aden). The most desirable trait passed along to these varieties is the ability to continually produce new flushes of leaves throughout the season...unlike H. sieboldiana. H. 'Sum and Substance' therefore will outgrow all other hostas, eventually producing a 9' wide mound (Wade Garden, Ohio).
The real excitement in fragrant flowering hostas came in the mid 1980's when a double flowered H. plantaginea was imported from China. Folks were gladly shelling out $200 per plant for a peek at this 10" long fragrant white double flower. The myth outlived the reality in this case, as the flower would only open if the temperatures were just right...not too cool and not too hot. The punishment was that the buds always formed and swelled, and right before opening...poof...a stem of limp petal mush.
Then came the two variegated edge plantagineas, H. 'White Shoulders' PP (white edge) and H. 'Heaven Scent' PP (yellow edge). These highly promoted new hostas with variegation and the giant fragrant flowers soon also did a belly flop. After H. 'White Shoulder' made it through one winter, it returned as H. 'No Shoulders'. After that, it wasn't long before this weak grower faded into the sunset. The same was true for H. 'Heaven Scent' as it too quickly found it's way out of gardens, replaced by varieties that actually grew. Only recently has a true variegated H. plantaginea entered the market with an edge that actually grows. H. plantaginea 'Ming Treasure' from Mark Zilis of Rochelle, Illinois promises to be that long awaited pot of variegation at the end of the rainbow.
THE BLACK SHEEP...THE GREEN SPECIES:
The more and more hostas that I grew, the more I longed to learn more about the species from which these hybrids came. All species are green and will sadly never encounter the popularity of their showier brethren, but each as something to offer. Some of my favorites are H. venusta and H. pulchella, two of the tiniest hostas with a mature clumps only 6" wide. H. nigrescens offers a wonderful tall vase like vertical shape that is seen in it's offspring H. 'Krossa Regal'. H. yingeri, only discovered on a remote Korean Island in the 1980's has splendid spider like flowers that far surpass any other flowers in the genus hosta. H. tibae with it's branched flowers scapes...now there is a trait for the breeders.
There is a virtually unknown group of hostas that grow on in cracks on rock cliffs, often near waterfalls.. This comprises some of the most elegant of the hosta species. These hostas have large thick leaves, often with white leaf backs for reflecting heat and sun generated by the rocks. This group includes H. hypoleuca, H. rupifraga, H.pycnophylla, H. longipes, to name but a few.
Another of the oldies but goody hosta species has got to be H. clausa. Although it has been in this country for over 100 years, it is virtually unknown and is the most asked about hosta in our garden. First of all, it runs...actually it gallops in the garden to form a 10' wide patch in 3-4 years. Secondly the flowers don't open, as indicated by "clausa" which means closed. Each swollen bud has the most incredible coloration...dark purple, fading to hot pink where the bud attaches to the stem. Imagine what would happen, if this ground covering habit could be bred into blue and gold leaf hostas...oh my my!
SPORT FISHING:
You are probably wondering where new hostas come from. Would it surprise you to know that well over half of the hostas in the market were found as "sports" or mutations on existing cultivars. A sport is where a hosta will actually mutate into a different color leaf pattern. For example a gold hosta may sport to a gold with a green edge, or any other number of color pattern changes. The reason that so many sports are found is that hostas are genetically fairly unstable...sort of like the folks that collect them. A new term has been coined for folks who intentionally indulge in this new and wildly popular pastime of looking through nurseries for these hosta mutations as "sport fishermen"
HOSTA SEX:
More folks are seemingly enchanted with growing hosta from seed. This has significant increased as folks more away from the "sterile" H. 'Undulata' selections. Just like people, hosta offspring will not look exactly like their parents. Sure, they will share a few of the same characteristics, but don't expect a series of great new hostas.
The first rule of thumb is that the leaf color of the seedling will be derived from the color in the center of the leaf of the parent plant (grandparents are included here also). Green hostas will usually produce green offspring, blue hostas will produce some blue, some green, and some gold offspring. Gold hostas will produce some of each also. Edged variegated hostas will NOT produce variegated offspring. Only hostas that have white streaks (streaky) in the center of the leaf will produce variegated offspring. White centered hostas will produce all white hostas which usually die in the seed pots due to a lack of chlorophyll.
In my travels to visit "hosta breeders"around the country, I was shocked to find that the term breeders was being used...shall I say, quite liberally. Gardeners who found hosta seed growing in their garden considered themselves hosta breeders...I think not. In reality, there turned out to only be a small handful of breeders actually making hosta crosses in the entire country. This is in sharp contrast to the daylily world, where everyone who grows daylilies is a daylily breeder. To avoid having 50,000 varieties, many of which are undistinguishable, I have strongly promoted my 10 foot rule of breeding. If a new plant cannot be recognized by name from a similar looking plant already in the trade, it should be discarded. Obviously, for this to happen, breeders need to have a good familiarity with existing varieties.
What is the future of hostas? The future of hostas is unlimited...both the exposure and the breeding possibilities. Imagine a plant that was not listed in the top 20 of the perennial popularity poll some short 15 years ago, but has been #1 for the last five years. This and there are still folks that haven't even heard of hostas. Consider red leaves and red flowers...how about hostas with fragrant reblooming hostas, how about hostas for hot climates such as Texas and Florida...how about slug resistant hostas? Do I think this is an exciting group of plants...you bet!
CULTURE:
The are few perennials that are as easy to grow as hostas...if you remember a few rules. Hostas like rich organic soils, prefer moisture, and plenty of light (without afternoon sun). Most hostas are found in prairie settings, and the ones that are found naturally in woodland settings look pretty poor. Morning sun is always best, as the temperatures are generally cooler at this time. As hosta leaves are large, they transpire more moisture when grown in more light. This simply means that you will need to apply more moisture to accommodate the increasing evaporation rate.
Hosta are heavy feeders. Ideally, an organic fertilizer should be applied in early spring, then again in mid summer. While hostas will grow without such care, there is nothing quite like a well grown clump.
PROPAGATION:
Hosta can be increased by dividing the clump. In the ground, the best time is early spring, when the new buds just begin to show. The clumps can be divided later in the season, but seem to suffer more later in the season. Large clumps can be quartered with an axe or sharpshooter shovel.
To divide the clumps further, remove them from the ground and wash the soil away. Using a sharp knife, the plants can be divided much smaller. You will quickly learn which clumps divide easily, and which are difficult. Also, not all plants divide at the same rate. A three year old clump of some cultivars may still have only 1 crown, while others may have 100 in the same time. This obviously is reflected in the cost of these varieties.
In container grown hostas, they can be divided from early spring thru September without any problem. The only time that I like to avoid is when then the new leaves have just expanded. I containers, hostas can be divided down to single divisions if watering is attended to afterwards.
For large scale production, tissue culture is the method of choice. As many "off types" are produced, a competent culling process is needed to assure uniformity.
Hostas can also be grown from seed (see "hosta sex"). Seed can be sowed outdoors in the fall, where they will sprout the following spring. Using this method, expect 3 years before the hosta seedling will flower, and 8 years before all of the mature characteristics will be evident. We sow our seedlings indoors under 24 hour lights in the fall (no dormancy requirement in hosta seed). By late summer, the new plants are flowering and will fill a gallon pot. Using this procedure, it will only take 5 years in the ground for the mature characteristics to show.
PESTS:
The worst pests of hostas are voles, slugs, and foliar nematodes. Slugs have not been a problem in our garden, due to our high population of toads. If you need to use slug baits, remember to apply them underneath rock, boards, etc. Slug bait should not be placed on top of the ground.
You know you have voles if your entire hosta clump disappears into a subterranean hole, or returns in the spring as a fraction of it's last years size. Voles (herbivorous mole relatives) are easy to control if you follow all three steps. First vole bait (rat poison) must be applied every 10 feet through the infected area. If you can find the runs, then apply the material there. If a run isn't evident, then put the material on the ground (they find your hostas don't they). Secondly, cover all of the bait, as the voles only feed in the dark. We like to use clay flower pots (it makes visitors ask questions). Thirdly, repeat the procedure in 2 weeks. This doesn't mean three or four weeks...TWO. If you follow this procedure, you will get rid of your vole problem.
Voles are most active in early spring and early fall. When we had severe vole problems, we applied the vole bait for two years (both in spring and fall) until the problem was eliminated. If you have pets, be sure and check with your vet as to the toxicity of the product that you use on your pet and other non- target species.
In 1987, we were the first ones to recommend mixing pea gravel into the soil for vole control at a national conference. This has now been spread around the world, but in all bizarre manners. Our original recommendation is to spread 1-2 inches of pea gravel (#78) washed stone over the planted area, then incorporate it to 10 inches deep. The sharp points of the gravel seem to deter the voles from damaging the plants. It doesn't kill the voles, it only moves them to another part of the garden.
A final pest that is of great concern are foliar nematodes. Since, 1992, we have taken a proactive stand on the elimination of this severe hosta pest. Many folks don't realize that they have foliar nematodes, simply dismissing the early leaf browning to weather. There is no complete chemical control, and these plants must be destroyed, and the nematodes are spread by splashing water. We are distressed that most of the hosta growers are in complete denial of this problem and are spreading infected plants around the country. Please inquire when you order plants from any nursery about their foliar nematode control program. When the symptoms are present in late summer, feel free to send us samples and we can confirm for you whether you have this problem. We thank you for your help in this matter.
For more information, we recommend the following books:
The Hosta Book by Paul Aden (Timber Press) - quite dated but a good introductory book for those just beginning in the hosta world
The Gardeners Guide to Growing Hostas by Diana Grenfell (UK via Timber Press) - the best on the market today for the average gardener/collector
The Genus Hosta by George Schmid (Timber Press)- unparalled life work on every facet of the genus hosta. This is my most valuable reference book, but it can be overwhelming to mere mortals. Gardeners with less than 100 different hostas...wait on this one.
The Journal of the American Hosta Society (see support groups listing in the table of contents) - a truly fabulous 2/yr publication of the society featuring color pictures and informative article. This is without a doubt the best publication of any plant society, and a must for anyone interested in hostas