Thoughts off the top of my head: August, 2011
As most of you know, I travel the hosta world each summer to see as many new hostas and hosta friends as we can. This summer I actually did travel the world to see hostas. (See the Dutch hosta article below.) In June I visited Birmingham for the Dixie Regional and then I attended the AHS National Convention in New England visiting Connecticut, Rhode Island, Massachusetts, and New Hampshire. Then, it was off to Madison, Wisconsin for the Midwest Regional. Two days after returning home, I was off to Waynesville in the North Carolina Mountains for one more little vending trip.
By then it was the third week of July when I usually give the old green truck a few months rest before heading out again for my fall lecture tour. The truck did stay parked in the driveway but in early August I boarded a plane and headed off across the big pond to see hostas, hosta friends, and do a little business in Europe. I will not bore you with all the details or describe the almost 3000 photos we took, but suffice it to say that our hosts, the food, and the hostas were all great. The air travel was, well, not so good.
All this in a roundabout way, (you should know how my mind works by now), brings me to how hard it is to grow hostas in the South. Tornados and hurricanes a side, summers are long and hot. It got hot here, (upper 90’s, low 100’s,) just before Memorial Day and stayed that way with just a couple of days here and there in the upper 80’s until the middle of August. Our hostas looked washed out from all the heat stress by the second week of June. Much of the South experienced the same type of weather with somewhat differing periods of extended drought.
Before I go any further I must say that I have the greatest respect for the hosta gardeners in Wichita and Dallas. Believe it or not, there are hosta clubs in both cities with members that are serious hosta gardeners. At the Dallas Arboretum and Botanical Garden, Jimmie Turner has set up hosta trials to determine which hostas prosper in the 110 degree heat, (123 degree heat index), that frequents Central Texas. I wonder if any of them look good this time of year. I think Wichita and maybe even Kansas City were worse. I do not think it cooled down back into the 90’s for weeks.
Ironically, we southern gardeners think we are doing pretty well growing hostas. The plants in too much light in the nursery are a little burned this time of year and some fungus has made a home in the dry brown foliage but the plants at home in the shade looked pretty good, until Irene came through and dumped a foot of branches everywhere. Everything looks stressed but 100 degree heat is equally tough on annuals, perennials, ferns, hostas, and the shade trees themselves. It is not until I go north and see hostas grown in cooler climes that I am reminded that hostas can be carefree, easy to grow plants that get bigger and bigger every year.
I do know if it is good luck or fate, but almost every time I head north to see hostas in the summer the weather cooperates. While it was 101 degrees at the nursery we almost froze to death in New Hampshire with morning temperatures near 50. England and Holland were a little warmer but a day in the 80’s signaled a heat wave there. Even the 90 degree heat of Madison was a pleasant respite from our oppressive heat and high humidity. Now I am not so naive to believe that it never gets hot up North, especially in the Midwest, but it does come and go, a few days of stress and then a break. Nighttime temperatures remain lower also. At the height of our heat wave it was 90 degrees at 11:00 at night and 100 degrees at noon the next day. Not much of a break for our poor hostas. Most of them just went heat dormant and fell prey to brown leaves and fungal invasions.
How is the best way to deal with a really hot spell, either prolonged or short lived. Water! We try to water in the early morning usually to keep the foliage dry during the night. This prevents disease and slug damage. In extreme heat we water twice a day, morning and evening. Your hostas are just surviving at this point so try to keep them as full of water as possible. No need to fertilize until it cools down in late summer, mid-August this year. If your hostas start to put out a few new leaves at this time a little liquid fertilizer will help them expand to a reasonable size. If your hostas are in pots and easily moved, keep them out of direct sunlight in the afternoon. Just an hour of direct sun when temperatures are above 100 degrees will burn many hostas.
Extreme heat in mid-summer is stressful for your hostas but unexpected high heat in late spring when the hosta leaves have not yet matured can cause much more damage. Remember light intensities in mid-May are the same as those in late July and they are the highest the last half of June. The combination of high light intensity and high air temperatures is a most disastrous combination. 101 degrees in June is much more stressful to your actively growing hostas that 101 degrees in August after they have bloomed. Watch the sun as it moves across the garden. A well placed umbrella in that hot spot for a few days may save the largest leaves from burning on your favorite hosta.
Hostas like warm temperatures, (high 80’s and low 90’s), and unlike hosta gardeners they love high humidity. It is only when the air temperature approaches our own body temperature that hostas and gardeners alike start to feel stress and begin to function at a much lower rate. The length of time that the temperature is extreme is also important. Plants need a cool nighttime rest period (dark period) to function properly and many think that it is the warm nights in the South that effect hosta health as much as the hot days. While containers solve many of the problems of growing hostas, (voles, water requirements and fertilization, and tree root competition), hosta roots remain cooler in the soil than in a pot. They do remain wetter in the pot however, and that may be more important than having somewhat cooler roots.
Hostas are drought resistant and they will survive the extreme heat, amazingly so. However, for hosta gardeners that fret over any little brown spot or pin hole in a hosta leaf, burned hosta leaves are catastrophic. If you are so afflicted, then cut the worst leaves off. Hopefully the hosta will then be encouraged to make a few more leaves, especially if it is early in the year, but also later after it has bloomed. The new leaves may be small so help them grow with a little liquid fertilizer as they expand. In late summer your heat stressed hostas may want to go dormant early. You can cut them back as all the leaves turn brown if you like. Remember, everything will look fresh and perfect again next spring, it always does.
As I traveled around this summer I was amazed how different the same hosta looks in different locations. It usually takes me a garden or two before I can adjust my hosta vision to recognize hostas that are familiar to me at home. For example, cultivars that have H. montana in their background, like ‘Blue Angel’ or ‘Frost Giant’ have leaves that are much rounder in New England, and also in old England and Holland than in North Carolina. At home their leaves are much narrower with pointed tips. Hostas are also generally more puckered, (the ones that are supposed to pucker), in the North. After the initial visual shock, my eyes acclimate completely and I am at home with these larger, more interesting leaves.
The same hosta cultivars are different sizes in different places, too. We all see this without any recalibration of our eyes. From region to region but also garden to garden in the same area, the same hostas naturally vary in size. Some of it can be attributed to culture, some folks use a lot of fertilizer, some do not use any, but there is something bigger here, I believe. I have decided that all hostas have an ultimate “natural size”. Having just become aware of this concept this summer, (it was probably induced by heat stroke), I do not know at this time that I can accurately describe the “natural size” of any of the hostas I grow in inches or centimeters.
In the garden at home our hostas are finding their “natural size” as I am sure they have in gardens five or more years old everywhere. This size is dependent on where they are growing, in sun or shade, in the soil or in a container, in a garden or a nursery. To be sure, to a great extent a hosta’s GPS location also determines its “natural size”. A hosta’s size is even determined by who grows it. My hostas may all be a little smaller than yours, (or larger), but they are just the size they should be considering where they are growing.
Some of our hostas are getting larger and some got larger but are now a little smaller. They change as conditions in the garden change. All this is natural, but even if conditions remain pretty much the same hostas will find their “natural size”. In good, (wet), years they will be a little bigger and in bad, (hot), years they will be a little smaller. If a bad year is followed by a good year, healthy hostas will recover and again fill their space. They will not however continue to get bigger every year as hosta collectors often expect once they have reached their “natural size”. It seems to take about four or five years to reach this mature size and then for the next ten or more years the hosta remains pretty much the same size, its “natural size”. Eventually old hosta clumps may die out in the center and need to be hollowed out with a bulb planter or they may wander aimlessly over a wide area in the garden. They may not.
This theory or philosophy of hosta size is for gardener assisted hostas. Every hosta gardener has his or her own philosophy of growing his own hostas. I think most want to grow them as big as they can. It is an idea passed down from the first hosta collectors who invented hosta tours. If I visit your hosta garden and your hostas are bigger looking than mine, then I am jealous and work to grow mine to the “natural size” that they grow in your garden. This is the bigger the better philosophy. A few gardeners want their hostas to remain smaller than their “natural size”, probably so that they can collect more and more. Confined to a small pot or watered only by Mother Nature, these hostas come back year after year hoping for better days. It is amazing though how well some hostas can grow without any fertilizer.
Given the fact that hosta gardeners all over the world grow their hostas a little differently and they all have unique set of environmental factors, it is only reasonable that the “natural size” of any given hosta will vary greatly. This is what makes writing descriptions for hostas so difficult. When “large, medium, and small” no longer suffice for size descriptions and actual measurements are required, to be honest, it all becomes guess work. Hostas are “naturally” taller in shade than in sun and taller in the shade in the North than in the shade in the South. These “natural” heights can vary several inches for larger hostas and more than you think for small and miniature ones. Registration descriptions try to deal with this but they are only “natural size” dimensions for the plants that the registrant measured. They say nothing about the “natural size” of the plant somewhere way across the country.
The hosta show has a competing theory to the “natural size” philosophy presented here. It establishes a standard or “perfect” size for at least hosta leaves if not whole plants. While based initially on the registered dimensions of the leaf, it is the size that a perfectly grown leaf of any particular cultivar should be. It creates a size “ideal” that gardeners try to match. If the “natural size” of your hosta leaf is too big or too small when compared to the “ideal” size then you lose grading points. Too much fertilizer can be just as bad as not enough.
This hosta show “ideal size” theory has lead gardeners to believe that all hostas, where ever and however you grow them, should attain the size to which the hosta was first described in its registration description. In theory it should get no larger either. Anyone that has grown hostas for more than a couple of years knows that sooner or later he or she will not only grow many hostas to a “natural size” much smaller than described but also some to a much larger size. This does not always translate into blue ribbons at the hosta show but it will get the attention of a fellow hosta lover that has struggled to the hosta you have grown so well.
I guess the moral of the story is that although size matters, it really doesn’t matter that much. What matters is the health of your hostas. Hostas can be undersized and well grown. They can be huge distorted monsters also. Mature hostas if healthy will be about the same size year after year. Abundant spring rain will make them larger while drought at the time they are growing rapidly with reduce their size. Supplemental watering will only help correct the lack of rainwater so much. There is really no substitute for natural rain, and the cloudy skies and high humidity that comes with it. What really matters is that your hostas are healthy and happy, and all this seems natural to me.
One more thought, hostas are really special plants, maybe uniquely so. Hostas are not “flowers” like annuals, daylilies, iris, and a host of other perennials. They are even superior to orchids that are ignored beneath the greenhouse bench until they present their incredible floral displays. Hostas are whole plants and we admire them not just when they bloom but the entire time that they grace us with their presence in the garden during the growing season. In fact, hosta blooms are often considered by some the ugliest part of the plant and are removed as soon as they appear. Hostas are the stars of the shade garden and our gardening companions.
Growing hostas is not just gardening either. I know all of you are not as involved with hostas as I am, (you could be, that would be alright), but in acquiring a new hosta we often acquire a new friend. Hosta folks are as special as the plants they love. My hosta friends are also as varied as the plants they grow. Some are collectors, some hybridizers, and some just like to play in the dirt. All are special in their own way as is the collection of hostas they grow. Some specialize in minis, some giant hostas. Some have hundreds of their own hosta seedlings some have just a few they prize highly. As I like to say on bus tours, “There is always something special to see in every hosta garden”; and often it is the hosta gardener.
Hostas and their caretakers have been so good to me. For 30 years now I have been invited to share the hosta gardens and nurseries of hosta growers far and wide. Hostas have become so entwined with the fabric of my life that growing hostas is no longer just what I do for a living but it has become who I am. I must say it is a pretty nice gig. No, I am not suggesting my hosta mania is suited for everyone but I do encourage you to jump into the hosta pond with both feet. (If you are already in the pond then, swim to the deep end.) The hosta world now holds much more knowledge than any one human brain can hold, so jump in, plants some seeds, sell a few plants, have your garden on tour, actively participate in your local hosta group or go to a regional or national convention, just once. I promise, you will be glad you did.