UF/IFAS Okeechobee County Extension Service

458 Highway 98 North

Okeechobee, FL 34972-2578

Phone: (863) 763-6469

E- mail:  dfculbert@ifas.ufl.edu

February 28, 2007

Feature Article - for release the week of March 4, 2007

Dan Culbert - Extension Horticulture Agent

 

Successful seeding

A visitor to our office complained that she was having difficulty getting her flower seeds to get growing.  Like many enthusiastic Floridians, rather than purchase the standard bedding plants, her wish was to grow some of the more unusual kinds of flowers for her Florida Yard.

The problem she was having was the newly emerged plants were rotting.  Seedlings need to be kept moist, but not so moist that root diseases take off at the same time.  This disease of the seedbed is known as damping off.  Today’s column is adapted from a bulletin written by Dr. Bob Black to insure that local gardeners have successful seeding.

Seed Selection

Most bedding plants are propagated from seed.  It is important to start with good seeds purchased from a reputable source. Choose fresh seed that have been stored in cool, dry conditions. 

When choosing seed, know where they will be planted -- in boxes, planters, containers or in ground beds.   Plants grown in containers require different cultivars than those put into ground beds.

Homeowners might select good varieties by observing the performance of plants grown in local neighborhoods. Information on annuals can also be obtained from our office – we can help you select and locate specific varieties which may do well in our area.

Beginning gardeners may want to choose fast-growing seeds that are easy to germinate.  As experience is gained, germination of more difficult to grow (and expensive) varieties can be attempted.  Our office has a bulletin that lists bedding plants according to difficulty of germination.  It also includes suggested planting dates, light requirement, optimum germination temperature, and length of time for germination.

 

The Dirt on Dirt

Germinating seeds in natural soils or native sand mixed with materials such as perlite and/or peat moss is not recommended. These materials are usually not sterile, and may be infested with nematodes, weeds, insects and fungal organisms.

Prepared growing media, known in the trade as artificial mixes, can be purchased at reasonable prices in garden centers. These mixes do not contain “real” soil and are usually sterile, light weight, easy to handle. They will have both good water holding capacity and will drain away excess water. Some of these mixes are Ready Earth, Pro-mix, Jiffy-mix and Metro-mix. In most cases, these materials contain fertilizers.  

A suitable potting material for seed germination is straight perlite or coarse grade vermiculite.  These work well if soluble fertilizer solutions will be used when growing out the seedlings.

The medium can be placed in a flat, pot or plastic container which has drainage holes.  If containers are being re-used, be sure that they are clean and sterile.  Soaking older trays or other home-made containers in a 1-to-10 dilute solution of bleach and water for 30 minutes will eliminate most of the problem organisms that may be sticking around.

A good method is to use new peat pots or other small containers that will be transplanted into the final growing area.  Fill the containers with the soil mix, but not quite to the rim.  Make shallow depressions in the soil medium approximately twice the depth of the smallest diameter of the seed.

Many seeds are quite small.  If placed on the soil surface, they may fall into the cracks and crevasses at the right depth. Sometimes a thin layer of fine vermiculite can be used to cover the small seed.   For larger seed, the general rule is to cover the seed to a depth of 2-3 times their size.  Thus, a one-quarter inch pea can be covered with a half-inch of soil.  Check the seed pack for more information.

Moist not Muddy

After sowing the seeds, water carefully. Artificial mixes that contain peat moss and are difficult to wet when dry.  Water should be slowly applied until the medium is thoroughly wet. A misting spray bottle works well for this step.

After planting seed, cover the medium with a sheet of glass, plastic wrap. For seeds which require compete darkness, use aluminum foil as the covering. The best way to germinate seeds that require light is to put the germination container approximately 18 inches below a fluorescent light.

Check periodically to see if more moisture is needed in the medium, and to look for signs of germination. Avoid tall and spindly growth common to rapidly growing seedlings by transplanting seedlings to small pots as soon as the first true leaves appear. The seedlings can be grown in these small pots until they are large enough to transplant to flower beds.

The germinating medium should never be allowed to dry, especially when seeds are starting to germinate. This will reduce germination. However, keeping the seedlings too wet is also a frequent mistake and is usually very costly.  The soil mix should be moist, but not excessively wet. Look at the pots daily and do not water if it is wet - but when you do water, allow excess water to drain out of the container.  Allowing seedlings to remain in water will drown their root systems.

Excessive water in non-sterilized soil and containers will lead to the growth of various soil-borne fungi, known as damping off.  These will turn the new white roots brown, and the seedlings will look like they are wilting even though the soil is plenty moist.  One this process begins there is rarely anything that can be done to save the seedlings. 

Some fungicides are labeled for homeowner use as soil drenches, but the damage will have already been done.  Another option is to plant seed treated with fungicides.  These seed will often appear pink or purple, and they should be marked as “not for human consumption.”  Remember - we are talking pesticides, so read the label and follow directions carefully.

I’ve placed more information on our Okeechobee web page, http://okeechobee.ifas.ufl.edu.  If you need additional information on successful seeding, please email us at okeechobee@ifas.ufl.edu or call us at (863)763-6469.  Local residents can stop by our office at 458 Hwy 98 North in Okeechobee, and visit our Okeechobee County Master Gardeners from 1 to 3 PM on Tuesday afternoons. GO GATORS!

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Trade names, where used, are given for the purpose of providing specific information. They do not constitute an endorsement or guarantee of products named, nor does it imply criticism of products not named. The Florida Cooperative Extension Service - Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research, educational information, and other services to individuals and institutions that function without regard to race, color, sex, age, handicap, or national origin.  Florida Cooperative Extension Service / IFAS / University of Florida.  Larry A.  Arrington, Dean.  Last update: 03/01/2007 .  This page is maintained by Dan Culbert.

references   

Black, R.J. Germinating Your Own Bedding Plants for the Florida Landscape (ENH27). Gainesville: UF/IFAS Florida Cooperative Extension Service, October, 2003. http://edis.ifas.ufl.edu/EP013  

Schroeder, Ed. Starting Seeds. Tallahassee: UF/IFAS Leon County Extension Service,1/25/07.  http://leon.ifas.ufl.edu/News_Columns/012507g.pdf

Welshans, Jennifer. STARTING TRANSPLANTS FOR SPRING GARDEN (HOME AND GARDEN COLUMN).  Kissimmee: UF/IFAS Osceola County Extension Service, 1/4/2004. http://osceola.ifas.ufl.edu/pdfs/Master%20Gardener/Archives/archives_2004/HG_StartingTransplantsForSpringGarden.pdf