“Southern gardeners are no pikers, by any means, lit growing iris,” says Boyce M. Edens, one of Atlanta’s and the South’s well-known iris specialists.
“In fact,” adds Mr. Edens, “the number of iris enthusiasts in the South is increasing so rapidly that not only many of the largest collections but also some of the most famous hybridizers of iris are now located in the southern states.”
Effectiveness Of Red Clay Soil
Mr. Edens, states that as growers keep testing the tall bearded iris in our red clay soils they are more and more convinced of the productivity of our much taunted red clay sod if it is properly broken down.
His method of breaking down heavy Soil is by first incorporating quantities of sand. Then additional quantities of wood earth and peat moss are added to the soil for several seasons until it is thoroughly incorporated.
The result is a highly productive, friable soil in which iris thrive.
Although Boyce Edens does not have a large plot of ground, he is excellent.
Use of what space he has for his tall bearded iris plantings. I noticed that his iris gardens are almost surrounded by tall trees.
When asked if they offered much competition he showed me a cement wail four or five feet deep in the ground that surrounded the iris beds on the tree sides.
This wall prevented tree roots from going into the garden and milling the iris of valuable food and moisture.
Then, in answer to my query about the amount of sun his iris gets, he replied, “My iris gets 6 to 8 hours of sun a day. That is sufficient for the tall bearded sorts here in the South. They thrive on it.”
Disease Control
It seems that iris borers and fungus diseases are the banes of iris growers everywhere, but not so in the Edens garden, particularly as far as the borers are concerned.
Boyce has very little if any trouble with this pest, for he is of the opinion that if the rhizomes are planted very shallowly, right on top of the ground, the borers don’t like the heat and dryness that they are subjected to by such a shallow planting method.
As far as disease control is concerned, he merely practices clean culture to ward off fungus attacks. His whole garden is a picture of healthy growth everywhere.
Superphosphate is highly recommended by Mr. Edens to supply iris with plenty of phosphoric acids which promotes a strong stem growth and a good flower set.
In addition, he uses a 4-12-4 or a 5-10-5 commercial mixture to supply a balanced food ration to his plants.
When it comes to dividing time in the Edens garden the last 15 days of July are the ideal time to make divisions in the Atlanta area.
With the flowering period over by the middle of May, his plants are allowed to rest for about 45 days before dividing.
Then, the soil is thoroughly soaked before the clumps are lifted to prevent them from being broken, which would happen in dry soil.
Hybridizing Iris
When I first spoke of iris hybridizing in the South I had in mind many well-known growers.
Mr. Edens is rapidly becoming well known in the hybridizing field and is now developing some very promising new varieties. He has hit upon a most successful method of obtaining high germination of his seeds.
Instead of letting his seed pods dry completely, he plants his seeds immediately after the pods begin to burst.
Germination as high as 65% percent has resulted from this method. That doesn’t sound like much of germination, but it is good for iris seeds.
The seeds are planted in a cold frame which is kept uncovered until the first freeze. Then, the soil is soaked down well before placing the sash on the frames.
Boyce keeps a complete record of all his crosses both as to parentage and as to germination.
He has a planned method of hybridizing wherein he selects parent plants to produce characters of the desired combination.
If a seedling looks promising, upon first blooming, it is grown on for several years more to test the permanency of the desired characters. All undesirable seeds are discarded at once.
Variety Selection For The South
Mr. Edens says that many of the old-time tall bearded iris are doomed, for the trend now is toward the newer pinks, yellows, and bronze types.
His garden reflects his opinion, for only the newest varieties are to be found there.
In addition to his favorite tall bearded iris, he is also quite fond of his new Abbeville or Louisiana hybrids which have made excellent growth and bloom in his garden.
He says that most of the dwarf iris are not very satisfactory in this section, but Iris cristata and cristata alba are the best of the dwarf types. He warned that they have to be grown in moist places.
The crested Iris tectorum is another popular type in southern gardens. It blooms just after the last of the bearded sorts have finished blooming, thus adding to the length of the iris blooming season.
For early bloom, the Dutch or bulbous iris are decided favorites for the South, for they can be grown successfully even in the lower sections of the middle South where the bearded types will not thrive.
The Dutch iris is popular as a cut flower crop in South Georgia and North Florida where it is raised in great quantities.
While speaking of Atlanta iris specialists I cannot overlook two good friends of Mr. Edens, E. Fay Pearce, and Milton W. Blanton.
Both of these men vie with Mr. Edens in growing the newest varieties—and they both concur with him in his ideas about general cultural conditions.
Mr. Pearce’s garden is on a very steep but heavily terraced slope. In spite of difficult topography of this sort, he has raised some of the finest varieties on his terraced plantings.
Mr. Blanton goes in not only for the newest varieties but also for the old ones as well. Life is making an interesting test plot of his spacious garden where he is testing as many varieties as possible for their adaptability to our southern climate and soil conditions. His collection now numbers over 700 varieties.
Experimental Effects Of Soil Reactions To Iris Growth And Color
Mr. Blanton is also conducting a rather new but most interesting experiment on soil reactions affecting the growth and color of iris varieties.
He has three test plots, one with acid soil, one with neutral soil, and the third one with alkaline.
He sets several plants of a single variety in each of these plots and then notes the differences in growth and bloom.
Many varieties are now under test, and we are waiting with great interest to see the results.
He says that his testing work has not gone far enough to make any definite statements about the effects of soil reactions.
To further carry out his experiment on soil reactions, Mr. Blanton is also checking soil types all over the country to determine the soil reactions in nurseries where new varieties have been and are being introduced.
He says there are wonderful possibilities for further research along this line.
Soil Reaction
Many of our southern soils are acidic. With this fact in mind, a great many gardeners have blamed this condition for turning their blue iris white after a few years’ growths.
Mr. Pearce has definitely dispelled this theory by saying that soil reaction has no effect on color changes like that.
Where gardeners have plantings of both blue and white iris of the old and almost native sorts, the blue ones bloom very early—in fact so early that opening buds are killed by late freezing weather before they begin to show color.
Consequently, only the white ones will show the color that season. Then, at other times, a spring freeze might miss the blue ones, but a later one will bite the white variety, thus reversing the predominating color effect in the garden.
This is his explanation and proof of the misbelief of soil reactions affecting iris colors.
Referring to Mr. Blanton’s plantings, it is most interesting to see his plot of Iris stylosa in full bloom in late December and January.
In the Atlanta area, this species provides much welcome color when other garden colors except green are decidedly lacking.
Mr. Clint McDade of Chattanooga was one of the largest growers of Iris stylosa, although there are a number of people in the southeast growing quantities of this species for mid-winter bloom.
So far, no mention has been made of the Japanese iris (Iris kaempferi), which is quite a popular species for southern gardens.
Growers plant this type not only for the additional variety of color and type of bloom but also to extend the flowering season of the entire iris family.
Japanese iris do very well in our southern soils which are generally partially acidic in reaction, a condition which seems to be quite suitable for this species.
As to the popularity of the Japanese iris, Mr. H. C. Bland, who operates the Swan Lake Gardens in Summerville, South Carolina, has perhaps the largest planting of Japanese iris in the entire country.
He says that the combination of moderately moist soil, good fertility, and good friable soil will result in the perfect growth of this iris.
Those who are interested in long-season blooming for the iris family could start with Iris stylosa 115 the first to bloom in the season.
This is then followed by the popular Dutch and English bulbous types, then the bearded, Louisiana hybrids, and Japanese iris, thereby bringing the iris season from mid-winter until the mid-summer months.