What I learned from the winter of 2002–2003
Although I am a rookie to the nursery business (13 years at this writing), I have been in the Green Industry since 1970. Except for the winter of 1986–1987, I think the winter of 2002–2003 was the worst in memory because of a combination of persistent cold temperatures with a significant number of days below ten degrees recorded, and the duration and amount of snowfall. Anyone entering this business since the mid-1980s may have been awakened to the fact that we cannot grow all the plants that we thought we could or that we have to make sure some plants are sited for protection from the severest winters.
Although we have over 20,000 square feet of poly houses for winter protection of containers, we are not container growers of plants for resale. We grow cans only for field liners. Therefore, my thoughts relate entirely to field production. Yet, when I read Dr. Gouin’s article in the Mid-Atlantic Grower about over-wintering containers and his predictions of dead plants in the spring, I felt mild chest pain. I rushed to dig out some houses to see what was left inside. To my surprise, I found drier than expected soil conditions and just knew I was in for a real heart attack come spring. For whatever reason, we only lost a hand full of plants. Now I feel stupid-lucky.
Unfortunately, the field situation is different. Just so I don’t forget, please remind me constantly that I WILL NOT grow Ilex ‘Nellie R. Stevens’ ever, ever, again.
Waverly Farm is sited in the really wonderful growing region that I refer to as the Buckeystown Valley. The valley is about four miles wide and was probably the flood plane of the Monocacy and Potomac Rivers a million years ago. The surrounding land is wide open and used for traditional agriculture and a couple hundred acres of sod production. The winds can be constant, sometimes requiring you to wear a life line some days when trimming trees. Not kidding, I have to lean into it some days just to stay something like erect. As a valley it collects cold. We frequently record temperatures ten degrees colder than Dulles Airport even though we are only fifteen miles apart to the north. I live twenty miles southeast of the farm and our farm plants are consistently ten to fourteen days behind the material at my home in the spring. We are growing zone 7, actually an a or b, but I am guessing when you combine temperature with wind, we must be more like a 6.
My observations from the winter are pretty straight forward with regard to plant damage. But how we got there requires a deeper look into cultural practices and plants that maybe should be taken off the list.
Broadleafs, specifically Ilex and Prunus laurocerasus, and evergreen needled plants such as x Cupressocyparis leylandii and Cryptomeria japonica ‘Yoshino’ were the hardest hit.
The Leylands are uniformly straw colored on the windward side or dead. The saleable Cryptomeria lost their leaders and new plants are mostly unsalvageable.
Prunus laurocerasus cultivars were severely desiccated with the worst in lowest or coldest spots, unable to ship.
Ilex observations are as follows from least to worst damage:
- I. ‘San Jose’ : untouched, bullet proof.
- I. ‘Dragon Lady’ : a little defoliation of stems generated in the fall flush but basically good as anyone would want, very saleable.
- I. ‘Blue Maid’ : same as ‘Dragon Lady’ but a little stem bending from snow load caused some plants to have discolored areas and some defoliation from the injury.
- I. ‘Golden Girl’ : same as above but stiffer stem structure prevented any snow load damage.
- I. ‘Dr. Kassab’ : somewhat more dieback on last flush but saleable.
- I. ‘Blue Prince’ : dieback on last flush and 10%+ defoliation but saleable.
- I. ‘Blue Stallion’ : more snow load damage than above, 10% defoliation but saleable for 90% of plants.
- I. ‘Blue Princess’ : variation in damage from perfect (10–20% of total) to 50% defoliation to severely defoliated, significant variation in the same row, plants most protected from the wind are least damaged, shipped 25% of orders, held balance for a spring flush, most plants rebounded within a few weeks into the growing season.
- I. ‘China Girl’ : complete lack of uniformity in damage, some with brown leaves to the ground, some with defoliation of last flush and some with virtually no damage; all in the same row, we have shipped some orders early and held other orders until more plants shape up; liners from spring 2002 are to be roto-tilled, I am unsure if we continue to grow—see notes below.
- I. ‘China Boy’ : not as hardy as his woman.
- I. ‘Nellie R. Stevens’ : total defoliation and 25% stem die back, will survive to see another winter if I let them.
- I. ‘Blue Angel’ : this should be grown in Florida although I have two plants on the north side of my home that would be fine if not for six feet of snow that slid from the roof.
- I. ‘Siberica’ : we routed out all the liners last year except for a few we forgot about and it proved again that it really belongs in the tropics.
I have some thoughts on all the damage beyond just a rotten winter.
First, I am humbled by how Mother Nature can effectively determine our fate. We are having a wonderful year due in most part because before I started growing, a wise old nurseryman told me to diversify the plant list. If not for the fact that we grow over 500 different plants, this could have been a crippling year.
Second, I believe we create some of the field problems with the unintended consequences of over-nurturing the plants.
I can only speak for our own situation and realize that a half mile down the road, conditions can be different. One of the reasons we bought the current site is due to the incredible soil quality. In 1996, the year we bought the farm, corn yield was 282 bushels per acre. That missed the state record for unirrigated corn that year by 3 bushels. The state average was 130 bushels per acre. I always talk about corn yield because of my agronomy education where we learned that corn yield is one of the universal methods of rating soil productivity in the U.S. Our soils are as good as they get. Therefore, my thoughts may have no relationship to sandy soils, heavy clay loams and so on. However, my thoughts may serve to provoke thoughtful analysis by anyone who cannot exactly figure out the complete riddle when things don’t go as they have before or as anticipated. Further, I realize my thoughts may be just a knee-jerk reaction to one severe winter.
We have 100% drip irrigation coverage of the farm and use the system to deliver fertilizer. Given that we have not had a good year of summer rain since we bought the farm, we have aggressively run irrigation continuously during the growing season except when we get an inch or more rain. Last year we shut down irrigation in early October due to adequate rainfall. As a result our 2002 water consumption was 33% below 2001’s consumption when we had irrigated late into the fall.
I am thinking that we need to stop irrigating broadleaves and evergreens in particular in mid-August, and then wet the soil in late fall if there is no rain so the plants go into the winter with plenty of moisture. The rationale is to force the plants into a hardening off period so they are better prepared for cold winters. By way of trying to maximize plant development, we fight the natural plant mechanisms by which they evolve into winter readiness.
In our situation, I think we can probably reduce fertility by 50–100% without any long-term loss of plant production once the plant is established. We have established about an acre of display gardens that represent some of the plants we grow for the purpose of fun and to be able to show a customer what a more mature plant looks like. All of the display plants received irrigation the first year of planting only and have never been fertilized. The hollies experienced absolutely no damage last winter even though their exposure is the same as the field plants. Growth rates for all of the plants, some of which have been in the ground for over six years, have been very normal to exceptional.
Due to dieback, almost all production hollies had to be trimmed before digging this spring which in all cases (except I. ‘San Jose’) resulted in the loss of one grade. Thousands of young holly plants in the ground for one to three have lost of all their 2002 growth. It seems to me the plants could grow somewhat slower over the course of the complete production cycle and still be larger at the end with less water and fertilizer—if in fact water and fertilizer are contributing to the problem.
In the early 90’s, when I was just starting out, I fertilized the nursery in the late fall or early winter with a source that contained 50% ureaformeldehyde (a very slow release source of nitrogen). We have in recent years changed the schedule to a constant but low dose of soluble nitrogen from spring through mid-July on the theory that constant spoon feeding during the growing season would be useful. Obviously, I don’t exactly know what all the issues are, but I am convinced that fertilizer will be off the menu this year except for first-year plantings and then just a low rate.
I have learned a couple of other lessons from the great winter of 2002–2003. When the shipping season is shortened to half the normal time due to a late spring, be sure your shipping company is elastic enough to work through it. Ours was and I am not giving out their name.
It’s also a good idea to be constantly acquiring the best people available. When crunch time comes, you don’t need any slackers. We couldn’t have a better, more reliable and productive workforce.
In closing, it’s also not a bad idea to have a good hobby when you are snowbound. When I couldn’t get into the fields for a month, I rediscovered my welding skills that got me through college and made some stuff for the farm. But I’ll save that for another article ...
Jerry
Postscipt—mid-August 2003. I wrote the above article for the Freestate News in late April. We stayed the course and have not applied any fertilizer this year. It has been a period of anxiousness. We have not irrigated any plants that were planted in 2002 or earlier. Of course we have had ample rainfall through the end of July. The results have been more or less what I anticipated. Plant growth in general has been normal to exceptional. The exceptional comes from above average rainfall and below average temperatures. If I think of it, I’ll update this again in 2004.