Report from the Southern Trials, Part II
Last month, we covered the results of most of our focuscrops for the University of Florida spring/summer 2003 trials. However, therewere so many great new plants as single entries in the trials that I reallyfelt we needed to cover them in a separate issue where there would be enoughspace to focus on both field performance and a little bit of cultureinformation.
In case you didn’t get a chance to read it lastmonth… The trials are planted each year into ground beds amended withmushroom compost at 1 yard per 100 sq.ft.; the pH of the beds ranges from6.2-6.7; and a thick layer of aged pine bark is applied after the soil isprepared. At planting, 72-cell liners are placed directly into the beds on12-inch centers, and 4 grams of Osmocote 18-6-12 is incorporated around eachplant. Plants are then watered-in overhead by hand, and subsequent watering isdone through drip tubes similar to commercial vegetable production irrigationsystems. Plants are evaluated every other week for initial flowering and peakflowering, evaluated with a five-point system and rated on performance,diseases, pests, etc. We do not apply any fungicides or pesticides, exceptglyphosate to control weeds. After the first weeks of planting, we also do notdeadhead, pinch or trim, unless an entry is so vigorous it threatens theratings of entries surrounding it. The trials run from approximately April 1 toJuly 31.
We only trialed four varieties this year, but I hope in the futurewe can trial even more of the diversity from this incredible tropical impactgroup. Again, these plants were planted from 72-cell liners, and most were over10 feet tall five months later. I was impressed with the overall speed ofgrowth, as leaf size on many cultivars exceeded 7 feet. Flowering would occurnext year, and so it is not part of our trial.
One of the most interesting bananas we had this year wasplanted in the landscape and not a part of the formal trials. This species,Musa velutina (Boondox Tropical’s), has been flowering for three months withbrilliant pink bracts and fruit. This particular plant was planted from a7-gal. pot, so it already had a year of growth behind it; we’ll be looking toformally trial this species next year.
Bananas are an underutilized annual for Northern markets.Because of its growth speed, Northern growers could start with liners and avoida lot of the shipping issues that occur when trying to move larger plants.
Varieties to consider: ‘Rojo’ (Agristarts) has dark purplemarkings that really stand out in plantings; the other cultivars were greenfoliage types. ‘Pace’ (Agristarts) received lower ratings because it was unableto support its own leaves (7-10 feet in length), and foliage bent at thepetiole throughout the season.
We are adding a larger component of native plants into ourtrials for a couple of reasons, and this year gave us some very good material.Part of the reason for native plants is the obvious connection to lowerirrigation, reduced chemical usage and an increasing governmental interest inthese plants. However, I wanted natives in our trials to see how they comparedto cultivars of similar species and hybrids where there has been a lot ofselection in the release process. There were a few real standouts in terms ofperformance and potential. There were also a few that lack either ornamentalqualities or were late summer to fall flowering and therefore did not fit wellinto the summer timeframe.
Coreopsis leavenworthii (Micanopy Wildflowers) beganflowering quickly after planting and continued to hold good color through mostof the season. The lanky growth habit will pose some problems for commercialproduction, but landscape habit and flowering were excellent. The native blanketflower, Gaillardia pulchella (University of Florida/IFAS-IRREC Collected) didso well, we are doing a focus trial of gaillardia next year to check out moreof the commercial hybrids.
We were lucky enough to get a couple of good native lantanaspecies this year, and I have inserted the ratings for some commercialvarieties intoFigure 2, bottom,to show how the native species compare. I was very impressed with Lantanadepressa (University of Florida-IFAS-IRREC), which has a flower color similarto ‘Gold Mound’, but with a more open habit and a lighter green leaf. Thesespecies could certainly be adopted immediately into landscape use in the DeepSouth. Lantana involucrata (University of Florida-IFAS-IRREC) has pale pinkflowers and a much lower color impact in the landscape, but the Á growthhabit was mounding and fairly dense, so it certainly has potential as well.Lantana ‘Morning Glow Orange Yellow’ and Pink Yellow (Bodger Botanicals) hadexcellent flowering and color, but the growth habit of Pink Yellow was a bitleggy so ratings were lower.
There is still a big difference in commercial cultivarsversus native species. Bodger’s two releases have much higher color and impact,but for growers looking to incorporate native species, there is definitely somepotential here.
‘Gold Flake’ mecardonia (Proven Selections) turned out to bemuch tougher than it looked. (Imagine a dichondra with brilliant yellowflowers.) I was really impressed with the performance and flowering season infull sun. Throughout the summer, the plant remained in bloom, and foliage heldup to summer rains. The natural foliage color is a pale green, but the flowersare striking. This would be an excellent component crop in mixed containers fora trailing growth habit. In shade, the plant lost its vigor, so in production,keep light levels high!
‘Festival Star’ (Proven Winners) baby’s breath is aheat-tolerant gypsophila, which as far as I know is a first. This is usually awinter annual in the South, but the dwarf cultivar has bloomed all summer andis self-heading, so old flowers drop off and new ones take their place
‘Ebony’ Eranthemum (Proven Selections) was also a pleasantsurprise. I was thinking all summer, “Why not grow a coleus instead?”as the somewhat glossy black foliage was nice, but the plant was less vigorousthan coleus and seemed to fit the same niche. That is, until it began floweringin small spikes of white flowers with pink centers — very cool. Plantsgrew to 3 feet tall and were very uniform. At least for us in the South, thelate-summer flowering is really nice! Having seen this plant in the trials oneseason, I can now see where it would shine. In mixed containers, the high vigorof coleus can overrun other plants. Ebony could provide contrasting foliagecolor without getting out of control. In production, keep this plant warm, asit did not grow much in the trials until night temperatures were above 65ºF.
Colocasia ‘Rhubarb’ (Proven Selections) predictably grewvery well. Like most elephant ears, it loved heat and moisture. The good partis that it doesn’t sucker, or at least hasn’t yet. In the Deep South, colocasiathat produce suckers are on the hit list of every invasive plant movement, sothis clumping characteristic, in addition to beautiful rhubarb-colored stalks,makes this a great addition to the landscape or large mixed containers. Leavesare a dusky gray green, but the petioles are, as the name implies, bright redwith subtle streaks of deeper colors.
Florida city series coleus (Lake Brantley Plant Corp.) hadsome great cultivars. As these are selected in Florida, it is no surprise theyhave heat tolerance, but the bright, clear red tones and the vigorous growth,which should translate into good growth for Northern production, are what Ireally liked. ‘Hurricane Louise’ (Hatchett Creek Farms) was last year’s bestcoleus for upright habit, good branching and no flowering. This year, it heldits own again, with a strong growth habit, tolerance of low water and only twoflower spikes out of 40 plants. Erika really liked ‘Stained Glassworks Copper'(The Flower Fields) for color and habit; I preferred ‘Gay’s Delight’ (ProvenSelections) because the growth habit was very compact and well branched.
In scaevola, flower size and late season performance reallyseparated cultivars, but ‘Brilliant’ (Horticultural Marketing Associates) and’Whirlwind White’ (Proven Winners) were both excellent and long lasting. Ithink the unique, somewhat upright habit of Whirlwind really sets it apart fromthe rest.
To get the full story of the trials, check the trials Website (http://hort.ifas.ufl.edu/floriculture/springtrials2003) so you cancompare what I say with data and digital pictures taken every two weeksÁ throughout the season. Also, due to the number of cultivars presentedhere, please use the Web site to locate sources for this material, as allentries on the Web site indicate the suppliers.
Author’s Note: We would like to thank all contributingcompanies and sponsors for their support of the 2003 spring/summer trials. Thelist is long and this type of trialing can only be effective with thecooperative efforts of our industry. Our main Floriculture Field Day will beheld May 19-20, 2004. The field day is held in Gainesville, Fla. and includestwo days of educational programs as well as trial garden tours.