Wednesday, February 25, 2015

Dew of the sea

Did you know that rosemary is in the mint family?  Did you also know that the Latin name for rosemary means “dew of the sea”?  There are probably a few things that you didn’t know about rosemary, but  you do know what a great herb it is across the board.  Rosemary is a very different type of herb as it is actually a small shrub.  In fact, I have seen gardens where rosemary was sheared into interesting shapes that bring an ornamental quality to the landscape.  Can you incorporate rosemary into your landscape?

Rosemary (Rosmarinus officinalis) is a small, hardy perennial evergreen shrub with small, narrow, spicy leaves on spindly upright stems.  In addition to the aromatic, needle-like gray-green foliage, small light blue/lavender or pink flowers appear in winter and spring.  Rosemary is a Mediterranean herb that is often used as a topiary, container plant, or landscape shrub.  Left to develop un-trimmed, rosemary can grow to six feet tall with a spread of four to five feet. There are many cultivars available including groundcover forms to choose from.   Standard rosemary can be clipped into a topiary of your liking by trimming every few weeks to encourage new, fragrant growth and to maintain a certain shape.   Keep in mind that rosemary is not just for the herb garden anymore!  Consider planting this hardy herb in the landscape in a full-sun area with well-drained soil and use it as a low hedge or specimen plant.  Regardless of where you plant it, every time you brush up against rosemary, that great appetizing and refreshing scent drifts into the air. 

Spot observations indicate that it is adaptable to Florida.  However, in our humid climate, rosemary is not as long-lived as you might think.  Accordingly, always have a supply of rooted cuttings ready to replace any specimens that have succumb.  Rosemary stem cuttings root readily so propagation is a breeze and tends to work better than starting from seed.

The fresh or dried mildly bitter-tasting leaves are the parts used in cooking.  Nutritionally speaking , rosemary is extremely high in iron, calcium, and Vitamin B6.

Whether you use rosemary specifically in herb gardens or slip them into niches in the landscape, inclusion of this edible ornamental makes for a more interesting and useful yard.  For more information on all types of herbs suitable to our area, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -

Vegetable Varieties for Gardeners (2008) Cornell Cooperative Extension.
Stephens, J. M. (2003) Herbs in the Florida Garden.  The University of Florida Extension Service, IFAS.
Naylor, C. Everyone Should Grow Rosemary.  The University of Florida IFAS Extension Service in Leon County.
Friday, T. (2006) Rosemary is for remembrance.  The University of Florida IFAS Extension Service in Santa Rosa County.
Jean Meadows and Mary King (2015) Food Fare -Rosemary.  The University of Florida IFAS Extension Service in Sarasota County.

Tuesday, February 24, 2015

The root of the problem

Roots are major organs that are essential to tree health.  However, they are often overlooked as construction, foot traffic or other soil compaction issues permanently damage a tree.  Where are the roots anyway?  How far out do they extend so that damage can be avoided? Can we manage roots in an urban environment full of sidewalks and pavement?  Research may show some insight to this hidden underground world.

Traditionally, a typical tree root system illustration would show a central tap root penetrating deep into the soil with side roots and fine roots extending out in all directions to the edge of the branch reach.    Some research suggests that in fact taproots may be absent depending on the species and other conditions.  As an example, oaks may have a taproot while maples will not.  Some taproots are cut at planting and are absent.  Urban trees in compacted soil often do not have a taproot.  It was also found that side or lateral roots are situated well outside the drip line.  In fact, many trees were found to have a root spread of three times the spread of the branches with most of the fine roots found only in the top twelve inches of soil - many of these roots were found in the top two to three inches.  Research showed that a Southern magnolia, for instance, had roots out to 3.8 times the drip line.

So what are the implications for working around trees and planning for root issues?  Trees that may appear to be well protected can still be damaged because the roots go so far out beyond the drip line.  This could influence construction site work, foot traffic patterns around urban trees and other considerations.  Trees that appear fine today may show signs of decline and death in subsequent years.  Can you imagine what the tree you just planted will look like in thirty, forty or fifty years from now?  Will it interfere with a sidewalk, a driveway or underground utilities?  In brief, trees roots in urban areas can be managed with techniques such as root barriers, engineered/structural soil, channeling roots, etc.  Florida Certified Arborists are good resources for assistance with this effort and can be located at the Florida International Society of Arboriculture -

Tread carefully around trees - their roots are essential for structural support and as organs to gather nutrients and water.  They must be protected and managed for the long-term health and safety of our urban forests. For more information on the best management practices for planting trees, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -


Gilman, E. F. (2014) Root growth on urban trees. The University of Florida Cooperative Extension Service, IFAS -
Gilman, E. F. (2005) Planting Trees in Landscapes.  The University of Florida Extension Service, IFAS.
Gilman, E. F. (2011) Dispelling Misperceptions About Trees. The University of Florida Cooperative Extension Service, IFAS.
Gilman, E. F. (2011) Where Are Tree Roots?  The University of Florida Cooperative Extension Service, IFAS.

Gilman, E. F. Gilman, E. F. (2002) Site Evaluation Form for Selecting the Right Tree for Your Planting Site, the University of Florida Cooperative Extension Service.

Wednesday, February 18, 2015

Florida-friendly landscaping™ is for everyone

Our yards are merely small models of the outside environment.  The water we use, the fertilizers we apply, and the pesticides we spray have influences in and potentially outside our yards.  The plants we select may also contribute to how much we use the aforementioned inputs.  Our landscapes tend to change over time; especially as to what is the best way to manage your yard.  Does your yard need a Florida- Friendly  Landscaping™ makeover? 

The Florida-Friendly  Landscaping™ program is an overarching set of horticultural concepts that enhances the community as well as protects the natural environment.  An FFL yard uses the nine identified principles that make up a no-nonsense landscape: efficient irrigation & water conservation, mulching, recycle, attract wildlife, "right plant, right place", integrated pest management, fertilizing properly, reducing stormwater runoff, and shoreline stabilization.  Again, many of these concepts are just good common sense.  Outdoor water conservation is a basic especially now when local rainfall is limited.  Water resources, especially water used for irrigation, should be used intelligently and with some knowledge of the plants we are growing.  Use water only when your lawn or landscape needs watering.  Many lawn and landscapes get over-watered making them less drought tolerant or prone to disease.  Keeping in mind local watering restrictions, many plants do well with about three-quarters of an inch of water per application.  Rain barrels are also good ways to catch and hold water for later use.  Hand-in-hand with proper watering comes mulching.  This technique uses various materials including organic matter placed around plants to suppress weeds and conserve water.  Recycling in the landscape includes composting and "grass-cycling".  Composting takes various raw organic materials allowing them to breakdown into a more stable, soil-like substance. Good organic mulches include pine straw. shredded melaleuca (FloriMulch®) and pine bark.  Compost is great for mixing with and enhancing garden soil growing vegetable and bedding plants. These mulches help retain soil moisture and slowly-release nutrients.  Grass-cycling involves returning the nutrient-rich grass clippings back to the lawn to provide some of the fertilizer turfgrass requires.  Mow regularly so that no more than one-third of the grass blade is removed at any one mowing.  These grass clippings will not contribute to thatch.  

Attracting wildlife adds another great feature to our yards. It may include something simply beautiful like attracting butterflies.  Selecting the right butterfly plants and adding a water feature will attract these insects.  Birds will also enjoy new water sources, new trees for nesting areas and native wildlife food plants placed throughout the landscape. 

When we say "right plant, right place" we mean sensible selection of plant material using knowledge of the plants and preferred growing conditions.  For example, a shade-loving plant like many types of ferns may not do well in a full-sun site.  A plant that requires a somewhat drier environment may rot in a site regularly watered to excess. A tree that may grow up to sixty-feet tall and over one-hundred feet wide would not be a good choice planted right next to a house.  Consider using Florida native plants as well. Get to know your plant material and analyze your site’s environmental conditions before you plant. 

Integrated Pest Management or IPM is another important component of a FFL yard.  Instead of blindly applying a pesticide at an unknown pest, it is much better, both economically and environmentally, to identify the pest, determine if there are sufficient numbers to warrant a treatment, and then select a treatment that is least-toxic or non-toxic with pesticides used as a last resort.  We are not looking at total pest elimination, just suppression to acceptable levels.   

Fertilizer is another landscape input that is often misunderstood and misused.  Slow-release fertilizer feeds plants over a period of time and stays put longer.   (Don’t forget our County Fertilizer Ordinance - ) Fertilizers that are lower in Phosphorus are also recommended as our Florida soils generally already have plenty of this nutrient. Try to select plants that have low fertilizer needs.  When you fertilize, water and manage pests properly, the chances of residues contained in storm-water runoff are reduced as well.  Downspouts can direct water into planting areas instead of a paved surface.  Small berms and swales can divert water from running from your yard.  Last, but not least, protect the waterfront!   Whether you live on the harbor, river or a pond, use FFL principals to protect these water resources. 

In the same vein of FFL, I would also like to introduce our new Florida-Friendly Landscaping™ Horticulture Program Assistant, Tom Becker.  Tom has been involved with Horticultural Extension work for most of his career ranging from Pennsylvania to Florida.  His expertise is in Florida-Friendly Landscaping™ and he has a wealth of information on plant selection, water conservation, cultural practices and landscape trouble-shooting, so please feel free to pick his brain!    You can contact Tom at our office at (941) 764-4351 or .    For more information on all types of gardening topics in Southwest Florida, please call our Master Gardener volunteers for gardening help on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -     I also want to direct you to our “ Master Gardener Speaker’s Bureau” at  where subject matter presentations can be scheduled for your group or organization.


The Florida Yards & Neighborhoods Handbook (2009) The University of Florida Extension Service, IFAS. -

Friday, February 13, 2015

Carefully prune palms - proper palm pruning is worth the effort!

A healthy, properly pruned palm is a joy to behold!   Healthy palms should have a full rounded canopy and not look like a feather duster!  Excessive pruning of palms is a practice that leads to reduced photosynthesis, nutrient deficiencies and a bad appearance – this happens way too often!  In fact, not all palms need to be pruned.  Let’s take a look at this important task and how it can be performed properly.

As mentioned, not all palms need to be pruned in the first place.  Palms that have what is called a crownshaft never really need to be pruned.  The crownshaft is a green smooth area located just above the gray portion of the trunk of palms such as bottle, royal and foxtail palms.  Normally, old fronds on these go from green to orange-brown to brown over a three-day period and then self-shed – look out below!   Old palm fronds that do not shed normally may be potassium deficient and stay in place for months.  Old fronds on palms that do not have crownshafts (Queen palms as an example) normally hang down against the trunk when dead and then can be pruned off. 

Excessive pruning really puts a monkey wrench into the photosynthetic and nutrient storage process.  While it is noted initially that over-pruned palms produce more fronds, these fronds are smaller and have less capacity to photosynthesize. Hand-in-hand with this issue, the trunk diameter begins to narrow as well.   Removing older fronds too soon can also deplete the palm’s reserve of nutrients such as potassium.  Older fronds translocate potassium to newer leaves to sustain them.  If an older frond that is a bit yellow or frizzled looking is removed too soon, potassium will be obtained from the next set of fronds within the canopy and these fronds will then begin to show nutrient deficiencies. 

Always clean tools between cuts with a disinfectant for five minutes so that you do not spread certain diseases such as Fusarium wilt from palm to palm.  Over-pruning can also attract insect pests such as palmetto weevils which may be lured in by the chemical scents of wounded palms.  

Prune palms at any time of year on an as-needed basis.  The best practices for properly pruning palms include the removal of dead fronds, and dead or living flower and fruit stalks.  If at all possible, leave discolored older fronds intact until they are fully dead and brown for the sake of the nutrients present.  As a reminder, the very best palm fertilizer analysis is 8-2-12-4 (which includes micronutrients) applied in November, February and May as per label directions, with an additional feeding of 0-0-16-6 in August.  Using the proper fertilizer is the best practice overall to prevent nutrient deficiency in the first place.  Keep in mind that a properly fertilized palm will retain more fronds in top condition for a longer period of time thus delaying the need for pruning.  If live green fronds must be pruned off, do not remove any leaves above the horizon line or, if you will, at the 9 o’clock and 3 o’clock position.  Cut fronds close to the trunk, but do not nick the trunk as this could become an entry wound for disease.  Also, do not use climbing spikes to get up into the canopy.  Trunk wounds will never seal up and again allow diseases to enter. 

Beware the ‘hurricane-cut”!  The “hurricane-cut” leaves only a few of the youngest fronds intact and does not protect the palm from severe wind.  In fact, observations suggest that “hurricane-cut” palms did worse in hurricane conditions than those properly pruned. 

Make proper palm pruning a standard practice in your landscape!  For more information on all types of palm subjects, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -


Broschat, T. K. (2014) Pruning Palms.  The University of Florida Extension Service, IFAS.

Wednesday, February 11, 2015

Success with flowering kale and ornamental cabbage

We have had a relatively mild winter so far, but here in Southwest Florida we can have occasional cold snaps that test our landscape plants from time to time.  As a result, we have to be careful what we use in flower beds as annuals.  One really tough and ornamental type of annual suitable to bear our winters is called flowering kale or cabbage – they actually only grow properly in the winter.  Very similar to our normal kale and cabbage, these plants produce colorful leaves that give a flower-like appearance. 

First appearing in seed catalogs in 1936, ornamental cabbage and flowering kale have been a welcome addition to brighten up the winter garden.  While normal garden cabbage makes tight round heads, ornamental cabbage forms a loose head with leaves developing into attractive colorful rosettes.  Leaf colors range from red and green, blue or white and green.  In temperatures below sixty degrees Fahrenheit, the color actually intensifies.   Flowering kale is similar to ornamental cabbage, but has finely-divided, frilly foliage.   Keep in mind that these plants don’t produce flashy flowers, just colorful leaves.  The true flowers of these Cruciferous plants are non-descript and unattractive.

While the ornamental cabbage and flowering kale can be easily started from seed, at this time of year it is just easier to purchase started plants available from many garden centers.  If you try starting these from seed in the future, allow two and one-half to three months from seed to colorful transplant – plan ahead.  Select a full sun area to plant and incorporate three to four inches of organic matter and about two-pounds of a slow-release general purpose granular fertilizer such as a 12-6-6 (or its equivalent) worked into each one-hundred square feet of bed space.  Set the transplants about eighteen inches apart.  After the plants are established use a liquid fertilizer as per label directions once a month.  Ornamental cabbage and flowering kale also do well in pots, hanging baskets, and larger planters.

Selecting your favorite cultivars may take some time as you explore the wide variety available.  Within the realm of ornamental cabbages, look at the various color series such as ‘Tokyo’, ‘Osaka’, and ‘Pigeon’.  Flowering kale is broken down into fringed-leaved cultivars such as ‘Sparrow’, ‘Chidori’, and ‘Kamone’ and the feather-leaved types such as ‘Coral Queen’, ‘Coral Prince’, ‘Red Peacock’ and ‘White Peacock’.   There are even long-stemmed types grown to be used as cut flowers such as ‘Sunrise’, ‘Sunset’ and ‘Crane’.

If you have not seen ornamental cabbage or kale, check out local garden centers or grow your own next year.  They take the cold and bring color to your flower beds.  For more information on colorful annuals, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -     Did you know that we are celebrating 100 Years of Extension in 2014?   The Smith-Lever Act of 1914 established the Cooperative Extension Service, which allows us all to benefit from the knowledge of our land-grant universities. Extension has helped millions of Floridians by tapping the latest information from the research engines of the University of Florida and Florida A&M University and converting it into practical knowledge we use every day.   In 2014, in Florida and across the nation, we celebrate the 100th Anniversary of the Smith-Lever Act by looking back on Extension’s record of service and educational outreach and by looking forward to the many challenges facing us over the next 100 years.


Gilman, E. F. (2011) Brassica oleracea Flowering Kale, Ornamental Cabbage. The University of Florida Extension Service, IFAS.

Gilman, E. F. (2011) Brassica oleracea ‘White Peacock’ White Peacock Flowering Kale.  The University of Florida Extension Service, IFAS.

Winter, N. (2007) Expanding winter selections by planting cabbage, kale.  Central Mississippi Research & Extension Center, MSU.

Smith, T. (2004) Greenhouse Crops and Floriculture – Flowering Cabbage and Kale.  The University of Massachusetts Extension Service.

Klingaman, G. (2000) Plant of the Week: Ornamental Kale, Flowering Cabbage.  University of Arkansas Cooperative Extension Service.  

Monday, February 9, 2015

Canna I grow it?

Perhaps one of the most popular and successful perennial flowers adapted to our hot and wet Florida climate are the cannas.  They not only have large flowers, some actually have colorful foliage.  From a short end of just under two feet to over six feet tall, cannas can make a great versatile and sustainable impact in your yard.

Cannas are tropical to sub-tropical perennials that have foliage similar to a banana.  As mentioned earlier, their perennial nature provides colorful foliage ranging from green to greenish blue and from purplish to white striped.  Add flowers that come in ivory, yellow, rose, salmon, crimson and red, and you have a plant that will improve the looks of any landscape.  Cannas are often used in borders or mass planted in round or square beds for a formal look.  Cannas will benefit from rich soil so consider adding several inches of well-rotted manure as you prepare the soil before planting.  They also like moist soil, even low-lying, bog-like conditions, so consider the location when planting.  Select a site that is full sun for best growth; some partial shade can be tolerated however. Cannas generally come as potted plants or bare-root rhizomes that are planted one to two feet apart depending on the ultimate size of the specific cultivar.  Start fertilizing cannas in the spring and then monthly as they grow throughout the summer with a 12-4-8 (or its equivalent) as per label instructions.  This supplemental feeding plus adequate water will help guarantee optimum blooming.  Careful removal of the spent flowers will help promote subsequent flowering throughout the season.

Also consider growing cannas in pots.  Four to five gallon plastic pots filled with rich soil makes an ideal setting for cannas.  Generally, less fertilizer and water is used, and exposure to soil-dwelling insects and nematodes is greatly reduced.  Potted cannas can be placed wherever you need them to brighten up a dull spot.  They can actually be buried up to their rims to blend in with the landscape. 

Besides dividing rhizomes, you can also grow cannas from seed – I have successfully done this.  As cannas seeds have a tough seed coat, soaking them in warm water for twenty-four hours helps speed and increase germination.  If the seeds are started early enough, you can actually get flowering-sized plants this summer. 

Beds of cannas quickly get overcrowded and will need rejuvenation each year.  Rejuvenation will allow for a clean-up of the bed and resetting of the best rhizomes.  Dig up the clumps and clean out the old rhizomes. Look for vigorous rhizomes which contain viable eyes (sprouts).  Clean the selected rhizomes and replant in the landscape or pots at once.

Selecting which cannas varieties to grow is a wide open task depending on your need and aesthetic tastes.  Keep in mind that there are two different kinds of flower types.  Flowers arranged close together are called "gladiolus flowering" cannas.  Loosely arranged, with narrow petals, the other type of cannas is classified as "orchid flowering".  Cannas are further classified into groups in consideration of their heights.  Very tall growing cannas are sometimes called giant cannas and are at least  four feet tall.  The next group of cannas are labeled as low growing and range from twenty-four  to about thirty-six inches.  The smallest group of cannas is called dwarfs and will grow to only about eighteen inches tall.  Select, mix and match your cannas as appropriate. 

Cannas rhizomes are available now in most garden centers around our county.  Seeds may have to be obtained through mail-order catalogs or through the Internet.  For more information on all types of gardening questions, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -   


Tjia, B. & Black, R. J. (2003) Cannas for the Florida Landscape.  The University of Florida Extension Service, IFAS.
Scheper, J. ( 1998) Canna X generalis., Tallahassee, Fl. 

Thursday, February 5, 2015

Please don’t worry about Spanish moss, ball moss or lichens

Sometimes immediate action is required due to an  imminent threat.    But when it comes to improperly identifying a problem in the landscape, maybe a case of mistaken identity for example, there may be cause to take a pause.    Take for example the questions we receive about lichens and/or Spanish moss, or ball moss  on trees - is it a problem, are they killing my tree?  The short answer is no.  These "clingers" are not parasitic and really do no damage to branches or bark.  They sometimes look unsightly and manage to scare homeowners into thinking that they are slowly taking over a tree.  Let's look at these misunderstood life forms and see what they are actually like.
Spanish moss is an epiphyte in the same family as the pineapple.  Also called bromeliads, these plants (not  really moss) cling to bark and branches as a support only.  No nutrients are sucked from the tree – they are gathered from the air and rainwater. Now, while a heavy infestation can reduce sun reaching the tree and/or cause twig breakage if wet and heavy, this is not the norm.  If necessary, Spanish moss can be physically removed.  Another related plant, ball moss, is an epiphyte that grows deeper into the tree canopy.  Interestingly enough, ball moss (as well as Spanish moss) can be an indicator of decreased plant vigor.  Ball moss benefits from a loss of a leafy canopy, it does not cause it.  Trees that are suffering from construction damage or cultural mistakes such as improper planting or pruning, may develop more ball moss than others.  This can be a red flag that something else is going on here – the ball moss is simply taking advantage of the open space and light. 

In the same vein of concern are lichens.  Many people believe that this organism is a disease of some type that requires control.  On the contrary, lichens, often grayish-green in color, are a very unique and harmless combination of algae and a fungus. This partnership is mutually beneficial to both parties as the fungus provides water, raw nutrients, and attachment, while the algae makes food via photosynthesis.  Again, this organism does not obtain any part of its living from the tree or shrub it is attached to.  Also, as with Spanish moss and their kin, lichens tend to increase on woody plants as available light increases.  There will always be a certain number of lichens on trees and this is normal.   A great deal of lichens may be a sign of a declining plant caused by other factors, but not as a result of the presence of lichens.  

In conclusion, Spanish moss, ball moss and lichens are generally not detrimental to the health of trees or shrubs.  Other stress factors such as root damage from construction activity may cause leaf lose which slowly  allows more light to penetrate resulting in an increased growth of these clingers.    So, don’t worry about them!  For more information on all types of things that are green, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Don't forget to visit our other County Plant Clinics in the area.  Please check this link for a complete list of site locations, dates and times -   

Arny, N. P. (1996) Spanish Moss and Ball Moss. The University of Florida Cooperative Extension Service, IFAS.
Gilman, E. F. (2011) Dispelling Misperceptions About Trees, The University of Florida Cooperative Extension Service, IFAS.
Brinen, G. H. (2006) Lichens.  The University of Florida Cooperative Extension Service, IFAS – Alachua County.