Monday, July 20, 2015

Got to love those heart-shaped leaves!

There are nothing like caladiums to brighten up a shady landscape!  Caladiums come in background shades of pink, red, green and white with similar color blotches and veins within the heart-shaped leaf.  These South American beauties adapt well to both an organic matter rich landscape as well as to pot culture and can be purchased as started plants or tubers.  Many cultivars are available within two distinct types - fancy and lance-leaf.  The fancy variety have the usual heart-shaped leaves, while the lance-leaf types have narrow leaves on short stems on an overall compact plant. New cultivars are released on a regular basis through breeding programs.  It would not be a Florida garden without some caladiums!

Let's start at the beginning with the tubers.  Interestingly enough, caladium tubers are graded and come available in different sizes like eggs.  While all size tubers are fine for landscape beds, generally, you want to choose a tuber size that fits the pot size if you are containerizing them.  For example, one "mammoth" tuber (which is three and one half to four and one half inches in diameter) fits well in a six-inch pot.  A "jumbo" tuber is two and one half to three and one half inches and is best started in a five-inch pot. 

Caladiums need a soil mix that is high in water-holding organic matter such as peat.  Drainage is also important with additions of sand or perlite.  A sterile commercial mix good for caladiums should be available at any garden center.  Proper soil moisture is very important because if caladiums are allowed to wilt, the plants may go dormant.   Plant the tubers upright (you may notice some sprouts already formed on the tuber) with one to one and one-half inches of soil over the top of the tuber.  Roots will form on the top and side of the tuber. While most caladiums thrive in either shade or partial shade,  some cultivars even do well in full sun if proper water is provided.  Also, plants grown in partial shade, for example, will develop deeper color than those in full shade.  Feed caladiums a balanced liquid fertilizer as recommended on the package.   After a nice summer of growth, if and when temperatures drop below 65 degrees F, caladiums will begin to go dormant.  The foliage will die back and the tubers will over-winter in the pots with some protection provided by storing them in a garage.  Those in the landscape are perfectly hardy and will over-winter on their own.

There are so many wonderful cultivars to choose from that to highlight any would not do this plant any justice – I don’t have a favorite, and I don’t know of one I dislike.


Evans, M.R., Harbaugh, B.K. & Wilfret, G.J. (2006), Caladium As Potted and Landscape Plants, University of Florida Cooperative Extension Service, IFAS.  
Gilman, E. F. (2014) Caladium xhortulanum Caladium.  University of Florida Cooperative Extension Service, IFAS.
Christman, S. (2003) Caladium bicolor., Tallahassee, FL. 

Black,  R.J. & Tjia, B. (2003) Caladiums for Florida. University of Florida Cooperative Extension Service, IFAS.

Tuesday, July 14, 2015

What, when and why

While many gardeners take the summer off due to the oppressive heat, rain and pests, there are some things that you can do now – plant, soil preparation, etc. that will take advantage of opportunities and help you target what is best accomplished on through July and early August.
Torenia - The Wishbone Flower
Many planting beds are looking a bit worn at this time of year and would appreciate some new plantings.  Keeping in mind bedding plants that can take the heat, humidity and rain, try some familiar plants such as coleus, vinca and celosia aka cocks comb.  For something different, try torenia.  Torenia is also known as wishbone flower because it has a unique wishbone shape in the center of each flower.  Torenia is tolerant of heat, heavy rains, and occasionally dry soils. Torenia flowers look a bit like a snapdragon and can be white, yellow, pink, violet, or purple, depending on the cultivar.  Some cultivars to look for are the Summer Wave® series including 'Amythyst Ice', 'Silver', 'Violet Ice', 'Large Amythyst', and 'Large Violet'.  Ornamental peppers also continue to perform well in our heat with bright colored fruits and foliage.  Some are actually edible, but often spicy.  Look for cultivars such as ‘Black Pearl’, ‘Calico’, ‘Purple Flash’, and ‘Sangria’.
Spearmint - Green and Ready to Grow
It is a bit hot now to try to start many herbs from seeds, but started plants of oregano, rosemary and mint are readily available at garden centers.  These perennial herbs will slip nicely into the garden and take right off.  Also, start thinking about your tomatoes which will go in late summer for the fall/winter garden.  Select varieties that you like or think that you might like to try and start the seeds now.  This may involve checking for seeds on-line for a greater selection.
 Oregano - An Aromatic Herb That Will Take the Heat
Not to think negatively, but having a Florida  International Society of Arboriculture (ISA) Certified Arborist check suspect trees for weak branches or hazards in need of corrective pruning could be considered at this time of year.  Many trees can be trained and pruned to better withstand windstorms in our area. 

If your lawn is not doing well, try to positively identify the problem before applying insecticides and fungicides willy-nilly. Lawn problems can range from mowing height issues to irrigation problems in addition to biological issues.  The first step in any Integrated Pest Management (IPM) program is to identify the pest, or the disorder, or the condition, etc., and then prepare to look at the remedy options.   

Take advantage of the sun!  There is still time to solarize your vegetable garden.  Weed seeds, nematodes, diseases and insect pests can be “cooked” out of the soil (at least temporarily) with this process.  It will take four to six weeks to solarize a garden, but it will pay off with sterile, pest-free  soil ready to plant. 

How many times have you seen an Irrigation system going off in the rain?  This maddening waste can be rectified with the installation of a rain shutoff device to save
money by overriding an irrigation system when it rains. If you already have one installed, make sure that it is operating properly.

Take some of these tips and suggestions to heart and enjoy your summer garden!  For more information on all types of gardening suggestions, 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 -

S. Park Brown (2012) South Florida Gardening Calendar.  The University of Florida Extension Service, IFAS.
Gardening Solutions. Ornamental Peppers (2013) The University of Florida Extension Service, IFAS.

Gardening Solutions. Torenia (2103) The University of Florida Extension Service, IFAS.