Garden Talk

with Rebecca Jordi


Leave a comment

Q:  Can I use 2,4-D to control weeds in my bahiagrass lawn?  

A:   The best method of weed control is to maintain a healthy, vigorous turf. Following UF/IFAS recommendations for proper fertilization, irrigation, and mowing will help to maintain a healthy lawn that is able to outcompete most weeds. However, if weed problems persist, the following chemical treatments may be used on bahiagrass for weed control when needed. Post-emergence herbicides are applied to weeds presently growing, it does not control seeds. Post-emergence herbicides (e.g., 2,4-D, dicamba, and/or MCPP) should be applied in May as needed for control of annual and perennial broadleaf weeds, such as knotweed, spurge, and lespedeza. Selective control of emerged grass weeds, such as goosegrass, crabgrass, or alexandergrass, can only be achieved by hand pulling. Sedges can be controlled with applications of halosulfuron. Drop off samples of your weeds for positive identification before applying herbicides. This is important to avoid improper application which wastes money and time – it does not help the environment either.  Apply herbicides only when adequate soil moisture is present, air temperatures are between 60°F and 85°F, and the turf is not suffering from water or mowing stress. Failure to follow these precautions will result in damaged turf. For information on controlling weeds in the lawn, please refer to ENH884, Weed Management in Home Lawns, (http://edis.ifas.ufl.edu/ep141). Many popular “weed-n-feed” fertilizers for home lawns contain the herbicide atrazine or metsulfuron. Both of these herbicides will damage bahiagrass; therefore, we do not recommend using weed and feed products on bahiagrass.  For these reasons it is critical to read the herbicide label.  Remember – “the label is the law.” 

Advertisements


Leave a comment

 Q:  My Italian cypress is dying and I want to replace it with a shrub that will stay thin.  Can you recommend something?

Italian Cypress

Italian Cypress

Podocarpus macrophyllus

Podocarpus macrophyllus

 A:   It is not uncommon for Italian cypress to start showing limb dieback especially if they are in the same irrigation rotation as lawns. These plants are drought tolerant and really do not need to be irrigated weekly.  My first thought is for you to consider a specific cultivar of podocarpus called Podocarpus macrophyllus var. angustifolius. This particular plant is a narrow, columnar tree with curved leaves, 2 to 4.5 inches long.  It is very hardy but you will need to cap the irrigation head for this area so it will also not develop disease issues.  


Leave a comment

Q: What is the bright yellow flower growing in the ditches now?

Swamp Sunflower

Swamp Sunflower

A:  Swamp Sunflower, Helianthus angustifolius, is a Florida native upright perennial potentially growing to heights of 4 feet or more. The dark green leaves are narrowly lanceolate and may reach a length of 8 inches. This spectacular fall bloomer bears yellow flowers with dark yellow or brown disks. In cold hardiness zone 8 seeds can be planted between May and July; for zone 9 planting times occurs April through August.  Swamp Sunflower grows best in full sun to partial shade and can be planted in a well-drained soil although it is native to low wetland areas. It appears to have fairly good tolerance to planting in typical garden soil but benefits from some irrigation in dry weather. If grown in partial sun, pinch plants twice in early summer to encourage branching. Swamp sunflower responds well to regular applications of fertilizer. Many plantlets develop around the base of the Swamp Sunflower; divide it yearly to gain more plants. Propagate by seed. Swamp Sunflower is susceptible to powdery mildew and spittle bugs.

 


Leave a comment

Choosing wind resistant trees

dsc04994editNow that Hurricane Matthew is gone and some of our trees came down there is often a “knee jerk” reaction to take all the trees down from around the house.  Perhaps we need to take some time and rethink this position because trees provide so much to us and the environment. If trees need to be replaced then let’s consider planting some tree with high to moderate wind resistance.

 

But, before I give you a list of trees to replant I want to mention we can make a good selection but do the wrong things to trees and alter their ability to withstand high winds.  Over-pruning trees or using improper pruning techniques will directly alter the trees ability to withstand storms.  Do not cut the top off the tree, no lion’s tail cut which generally removes the interior foliage.  No over-pruning to “raise the canopy.”   Be sure to call a certified arborist to prune trees.  Planting trees too deeply will show limb dieback on the tree very early.  Over-mulching – NO mulch volcanoes, mulch should only be 2-3 inches deep and never be close to the trunk of any tree of large shrub.  Over-watering – we should not water trees and shrubs the same way we water grass.  After a few years the trees and shrubs do not need irrigation unless we do through a drought period.  Growing grass up to the trunk of the tree – grass and trees are terrible partners.  The things we do to grass we should never do to trees.  Leave as large an area as possible with no grass.  Planting large shrubs around the base of the tree is a poor practice.  Adding soil to the roots of the tree – even a few inches can cause a loss of air around the roots.

 

This following information was taken from research done by the University of Florida in 2005 titled, “Selecting Tropical and Subtropical tree species for wind resistance.”

 

  1. One of the most important findings is the rooting space: the more rooting space that a tree has, the healthier it is, meaning better anchorage and resistance to wind.
  2. Trees growing in groups or clusters were also more wind resistant compared to individual trees. This might be an especially good strategy for tree establishment in parks or larger yards. Especially significant for those green belted areas.
  3. Proper should be considered an important practice for tree health and wind resistance

 

This list is not all of the trees but it will give you a good place to start:

Highest wind resistance for North Florida:

Carya floridana, Florida scrub hickory; Conocarpus erectus, buttonwood; Ilex cassine, dahoon holly;

Lagerstroemia indica, crape myrtle; Magnolia grandiflora, southern magnolia; Podocarpus spp, podocarpus; Quercus virginiana, live oak; Quercus geminata, sand live oak; Taxodium ascendens, pondcypress;

Taxodium distichum, baldcypress; Butia capitata, pindo or jelly; Livistona chinensis, Chinese fan; Phoenix canariensis, Canary Island date; Phoenix dactylifera, date; and Sabal palmetto, cabbage, sabal.

 


Leave a comment

Q: I am thinking about putting in small clumps of Elliot’s Lovegrass. Do you think it will do well here in North Florida?


elliots_lovegrass_ufifasA:  Elliot’s Lovegrass, Eragrostis elliottii, is a beautiful native fall blooming grass growing about 2-3 feet tall with the same spread. Elliot’s lovegrass is found among flatwoods, sandhills, and prairies from summer through fall. There are 30 varieties and species of Eragrostis in Florida. The pretty white seed heads bloom late summer to fall and are a good source of food for many local birds. The foliage is green but the flowers are an inflorescent white to tan with a shiny covering which sparkles in the sunlight – I know, I am waxing poetic now!  Like so many other ornamental grasses – Elliot’s lovegrass prefers full sun to very light shade and dry, well-drained soil. This will be significant when choosing a planting site as it should not receive irrigation typical of lawngrass.  Watering twice a week will kill it.  Elliot’s lovegrass is extremely easy to care for and requires little or no maintenance once established.


Leave a comment

Q: What is the name of this weed I found in my lawn grass?

florida_bellflower_ugaA:  It looks like Florida Bellflower, Campanula floridana, which is native to FloridaIt is a perennial wildflower which makes it more difficult to control as it propagates by rhizomes and seeds. This wildflower can root at each node making it a proficient grower. Florida Bellflower is often found in over irrigated lawns, moist areas or poorly drained soil.  It has small purple flowers bloom year round. Florida Bellflower grows up to 12 inches tall and about 6 inches wide; tolerates full sun to partial shade. Typically found in cold hardiness zones 8-10.  Best management practice is to reduce water as it cannot tolerate dry areas. Chemical management can be done by applying atrazine in October and March to control seed production.  While I know you are not happy with the plant in your lawn, it might not be a bad plant for those areas near retention ponds to help reduce erosion


Leave a comment

Q: Are there any heirloom hot peppers?

Chocolate Habanero

Chocolate Habanero

A:   Yes, we have many heirloom hot peppers which can be grown in several parts of Florida. Remember, the term “heirloom” vegetables means you can use the seeds from the fruit and produce future plants year after year. Hot peppers are native to Central and South America where they have been part of the human diet for thousands of years. Hot peppers were named by Christopher Columbus who mistakenly thought they were related to Piper nigrum or black pepper because they had a similar pungency. Columbus returned to Spain with some of the peppers, and its popularity rapidly spread throughout Europe, India, China, Korea, Thailand and Japan. Hot peppers are known for their pungent flavor. The pungency is caused by the compound capsaicin, which is measured in Scoville heat units. A pepper with more capsaicin will have a higher Scoville heat unit. Bell peppers have a Scoville unit of zero, while the hottest peppers have a Scoville unit greater than 1,000,000. The pungency level is genetic, but it can be influenced by environmental stress. A hot pepper from the same variety grown in hot, dry conditions would have higher capsaicin and a more pungent flavor than a hot pepper grown in cooler, humid conditions. Heirloom hot peppers are closely related to other vegetables in the family Solanacea, such as potatoes, tomatoes, tobacco, and eggplants. This means the same diseases commonly found on Solanacea plants will attack peppers. A few of those diseases are bacterial leaf spot which shows up as small, water-soaked or greasy spots on leaves. These spots are often accompanied by small, light green, raised spots on fruit which ultimately become enlarged and turn scabby. Viruses can also be found on peppers such as pepper mottle, potato virus Y, tobacco etch, and tobacco mosaic virus. These diseases create stunted plants, fruit and leaf malformation, mottling, and leaf mosaics, but it is really tough to identify these viruses in the field.  Most often, specimens need to be sent to the University of Florida pathology lab for absolute identification.  Controlling weeds and insects is a critical strategy for managing the spread of the diseases.  Remember to avoid overhead irrigation, and reduce handling, harvesting or pruning plants while the plants are wet. The attached publication from the University of Florida provides a long list of heirloom peppers to try.  Plant peppers in full sun and only in the warm months of the year.  http://edis.ifas.ufl.edu/hs1244