Woody Ornamental Production

 
The Jasmine Project

Production of Groundcovers for   

Instant Landscape Appeal*

Executive Summary

Richard C. Beeson, Jr. Ph.D., Mid-Florida Research and Education Center,

IFAS, University of Florida.

Gary W. Knox, Ph.D., North Florida Research and Education Center,

IFAS, University of Florida.

Sydney Park-Brown, Ph.D., Hillsborough County Agricultural Extension Service,

IFAS, University of Florida

 

*Project funding supplied by Tampa Bay Water.

The goal of this project was to produce an easily installed jasmine product that would provide an appealing "instant landscape" appearance. Asiatic jasmine was chosen because of it’s excellent performance history in landscapes throughout most of Florida. Its has the potential to lower supplemental irrigation and chemical inputs to near zero where it is installed. The project had three objectives: (1) to produce Asiatic jasmine as 1ft wide by 2 ft long by 2 inch thick slabs that could be shipped on pallets and installed like turf grass sod, (2) to successfully install the jasmine slabs in landscapes, and (3) to gauge the receptiveness of building professionals and the general public to using Asiatic jasmine as an alternative to turf grass.

Initially six blends of pine bark fines, Florida sedge peat and coarse sand were evaluated to select the two best for testing under production conditions. The two growing substrates selected promoted similar shoot and root dry masses in small tray trials, and had higher qualitative ratings and dry masses than the other four substrates tested. However, these two substrates varied greatly in air porosity, water holding capacity and bulk density. The two selected were a 60% pine bark: 30% Florida sedge peat: 10% sand blend (Bark),

                                                                                                                                                     
and a 25% pine bark: 25% Florida sedge peat: 50% coarse sand blend (Sand).

                                          

In February 2001, raised beds 2 ft wide by 15 ft long by 2 inches deep were fabricated and placed in 16 replicated overhead-irrigated production pads. Each pad contained six raised beds.

                                           

 Each growing substrate was used to fill all raised beds in 8 pad areas. Beds were transplanted with rooted cuttings of two Asiatic jasmine cultivars, ‘Minima’

                                            

and ‘Texas Long Leaf`.

                                            

Four pad areas of each growing substrate were transplanted with each cultivar. Within each pad area, three of the six raised beds were underlain with an organic erosion mat.

                                            

Also within each pad area, the jasmine rooted cuttings were transplanted at 1.0, 1.5 and 2.0 cuttings/ ft2 of bed area, such that each density was represented in a raised bed with and without an erosion mat. Each pad area was irrigated independently. Irrigation volumes were based on the previous day’s micro-climatic factors (temperature, humidity, solar radiation, wind movement and rainfall) and were computer controlled. Raised beds were sampled monthly to quantify root growth. In early January 2002, final samples, consisting of one square foot sections of the beds, were removed and shoot and root masses quantified.

Of the two cultivars, significantly more shoot and root growth occurred from the ‘Minima’ cultivar than the ‘Texas Long Leaf’ cultivar. Greatest shoot and root growth also occurred at the 2.0 plants/ft2 density than the other densities. Beds planted at the 1.0 plant/ ft2 did not fill in the beds sufficiently with either shoots or roots to permit harvest. By harvest, the organic erosion mat had completely decomposed and was useless.

In mid-January 2002, 900 ft2 of beds containing the ‘Minima’ cultivar were removed from the production pad, sliced into 1 ft x 2 ft sections, stacked on wooden pallets and transported to a model home at Fish Hawk Ranch, Eagle Ridge subdivision in Southeastern Hillsborough County. A month later, in February 2002, slabs of the cultivar ‘Texas Long Leaf’ were similarly harvested and transported to the Hillsborough County Cooperative Extension Service office in Seffner. At both sites, jasmine was installed like turf grass sod. Slabs were lifted from a pallet and laid on the ground. Jasmine at both sites were overhead irrigated initially after installation.

                      

Slab production of Asiatic jasmine was of limited success. The slabs produced did not have sufficient interweaving roots to firmly hold the slab together. During slicing of the15 ft long beds, unacceptably high percentages of shoots and roots were lost. As a result, the slabs were not the intact 1 ft x 2 ft sections sought. Slabs of the 1.5 plants/ft2 density and those in the Sand growing substrate were the worst. The best slabs were those grown in the Bark substrate at the 2.0 plants/ft2 density. Because the slabs were not intact, installation was slow and installed square footage was reduced to two-thirds that of the original bed area harvested. These characteristics were consistent across cultivars and installation sites.

Beginning about six weeks after installation builders, realtors, and visitors from the general public to the model home at Eagle Ridge, completed a survey querying them of their opinions of the jasmine beds. The majority of the respondents viewed the jasmine installation favorably. Building professionals most often cited greater aesthetic and more favorable economic considerations (lower irrigation and chemical inputs) for the jasmine beds compared to turf grass areas. In contrast, a simple majority of the general public thought the jasmine beds were less aesthetically pleasing than turf grass lawns. However about two-thirds of the general public respondents cited lower long-term maintenance of jasmine areas as reason to prefer it as an alternative to an entire turf grass lawn.

In conclusion, there are sufficient benefits, such as lower landscape water and pesticide applications, and interest from building professionals and general public, to justify continuing the pursuit of the goal of this project, i.e. to produce an easily installed jasmine slab that provides an "instant landscape" appearance after installation. On the production side, there are several important, but less critical, problems that should be solved relatively easily through further research. Critical problems stemmed from the loss of shoot and root mass with harvest. These losses magnified weak binding of a growing substrate by roots, and greatly diminished the quality and appearance of canopies. Possible solutions have been formulated and described. On the landscape side, information is entirely lacking as to how much and how long jasmine slabs should be overhead irrigated to achieve establishment.