Okeechobee County sealUniversity of Florida Extension ServiceUF/IFAS Okeechobee County Extension Service

458 Highway 98 North

Okeechobee, FL 34972-2578

Phone: (863) 763-6469

E- mail: okeechobee@ifas.ufl.edu

June 27 , 2011

Quick Links:  Variety Trials    Heirloom Varieties    Open- Pollinated vs. Hybrids    Variety Recommendations   Seed Sources   References 

For Release: June 29, 2011 

Dan Culbert - Extension Horticulture Agent 

Heirlooms - and other Seedy Words

Recently a visitor asked a question about “heirloom seeds.” Gardeners may have heard the term, but may not have a good idea of what it means. Knowing a little bit about how seed are produced can improve the chances of success in the garden.  It’s the focus of this column on seedy words.

The first seedy words to know are a culti-vated var-iety or cultivar. This is a plant that has been selected for its desirable characteristics that make it different from others. Those differences can be passed on to new plants by their seed or though cuttings or other means.  


The Trials

During my time at the University, I “helped out” several researchers with variety trials. This is where different cultivars of the same kind of plant are grown under the same growing conditions.  Measurements are taken on such things as the first date of harvest, the number and size of the product, their ability to resist pests, and sometimes a visual appearance rating was made – i.e. looking for the perfect “10.” 

Trials may be duplicated in different areas and over different years.  The cultivars that do the best are the ones that are recommended.   It takes time and money to conduct these trials. When funds are not available for these kinds of investigations, new varieties may not be adequately tested and recommendations may not be offered.

EX 01420200, a Seminis  fresh market tomato was developed by  Monsanto for consumer acceptance and disease resistance.  It is intended  for commercial spring planting in south and central Florida.   Photo: American Vegetable Grower.  Commercial tomato production in Florida: the varieties grown are based on the results of research trials.  Photo: Les Harrison, UF/IFAS  Heirloom Tomato variety display: cultivars are evaluated on consumer qualities as well as production capabilities.  Photo: High Mowing Organic Seeds

Heirloom Varieties

Several years ago, when considerable interest in heirloom vegetables appeared, UF vegetable crop researchers performed a variety trial of heirloom tomatoes.  They wanted to see how these tomatoes could hold up under large-scale commercial production.  Their conclusion was:  “Many [heirloom] varieties may be suitable for Florida home gardens and a few may be appropriate for our commercial markets.  [However,] commercial heirloom growers must be aware of the considerable fruit quality, harvesting, and shipping constraints associated with heirloom tomatoes.”

What is this term heirloom? According to one reference, a plant must meet three criteria to be considered an heirloom variety: the variety must grow “true to type” from seed saved from each fruit; seed must have been available for more than 50 years; and the variety must have a history or folklore of its own.

So what does it mean to be “true to type”? This means that the plants will show the same color form, shape, taste, plant growth characteristics and even pest resistance among all examples of that variety. For example, while there could be some slight differences, you can depend on a Purple Cherokee Tomato to grow as an indeterminate vine-like habit, have a unique maroon red colored fruit with a flattened beefsteak tomato shape, and normally mature with a tomato size of about a pound.   

Cherokee Purple is an heirloom Tomato variety.  The color is unusual,  the taste is different and the seed can be saved.  Because of root problems, commercial growers may resort to grafted tomato plants.  Photo: Peter Nitzsche, Rutgers Cooperative Extension Inbred lines (left) of corn (maize) are cross-pollinated to produce a hybrid offspring (right) that shows marked increase in vigor and crop quality. Photo: Uplingen Plant Science Garden Golden Bantam Sweet corn is an open-pollinated cultivar that was introduced by W. Atlee Burpee in 1902. Photo: Urban Farmer Seed Co. 

Open pollination and Hybrid vigor

Heirloom vegetables are also open-pollinated or non-hybrid.  These cultivars are produced by self-pollination or by repeated crossing to the same parental type.  The seed they contain can be saved from fully ripened fruit, and when grown in the following year, they will produce fruit that will resemble the parents.

Another kind of variety is called a hybrid - a variety that comes from crossing two different inbred parents that differ in one or more characteristics.  Inbreds have been allowed to only reproduce with the same parents over several generations. With each resulting generation, these plants often become smaller, less vigorous and less productive.  Why do this?  When two unrelated in-bred offspring are finally allowed to cross with another inbred line, a magical explosion of crop strength and growth - “hybrid vigor” - is the result.

The vigor of hybridization allows yields to increase, pest resistance to be added, and it may include other desirable characteristics which can improve the crop.  Some have credited crop hybridization as a prime reason for our country’s ability to feed larger populations with fewer farmers. 

A down side of hybridization is that if you collect and save the seed from a hybrid variety, its offspring will show a loss of that hybrid vigor – it will start to revert back to its inbred parents.  The result is, if you want the vigorous capacity that comes with hybrid varieties, don’t save the seed for replanting.  You will have to buy seed from seed companies instead.

But there are other down sides to saving seed too.  Seed can transmit various diseases from one generation to another, both from outside the seed coat and within the genetics of the seed.  And seed need to be appropriately handled and stored at correct temperatures and humidity or they will die.  Some seed store well over several years, while others have a short “shelf life” and need to be used promptly.   

Some gardeners and consumers choose to use “organic” vegetables.  For vegetable farms that are growing organic produce, they have to use organic seed.  This means that the vegetables that were grown to produce the seed crop also had to avoid synthetic pesticides and fertilizers, and must avoid the use of genetic modification techniques.  Generally speaking, organic growers use open pollinated (i.e. non-hybrid) varieties, and in some cases they may also use the old time heirloom varieties.  Growing vegetables for seed means longer growing seasons and increased exposure to pests - and increased challenges if organic methods are to be used.   (A UF bulletin is available that outlines how this is accomplished.) 


Variety recommendations

Back to the beginning: The visitor specifically wanted to know what kinds of heirloom seeds would grow here and what they needed to do to successfully grow them.  I think what he really wanted to know is if there were any recommendations for heirloom vegetables adapted to this area and if their culture would be any different than other vegetables.

One of the challenges of home vegetable gardening in Florida is that there is limited information on which cultivars do best in our area.  Looking over seed catalogs and garden center advertisements gets gardeners excited about new varieties.  The real questions are, will they do well under our growing conditions, and, are they available to us when our growing seasons appear. 

UF recommended varieties of Florida vegetable varieties can be found in our Extension bulletin, Florida Vegetable Gardening Guide.  If you grow vegetable garden you need a copy, available at our office - or it can be found online - http://edis.ifas.ufl.edu/vh021

In the case of tomatoes, some varieties are identified as heirloom vegetables.  I’ll be examining the other UF home garden varieties recommendations in the next few weeks and identify which of these are considered heirloom vs. hybrid vegetables.  I will make that information available in a future article if there is interest.

And if you need some suggestions for sources of heirloom vegetable seeds, I will add a few of these to the references at the bottom of the on-line version of this news article at http://okeechobee.ifas.ufl.edu. Our phone number is (863) 763-6469, and you can email us at okeechobee@ufl.eduGo Gators! 

Seed Sources

Seed Databases and Resource Guides

NCAT's Organic Seed Suppliers Search           OMRI's Organic Seed Database           Resource Guide to Organic & Sustainable Vegetable Production - ATTRA 

Selected Seed Companies:

http://www.seedsofchange.com/default.aspx      http://www.cooksgarden.com/?cid=PPC        http://sustainableseedco.com/  http://www.victoryseeds.com/  

http://www.highmowingseeds.com/             http://www.ufseeds.com/index.php        http://www.burpee.com/heirloom-seeds-and-plants/


Oshkosh Seed Company - old print Rutgers Tomato - Seed Package Old Vegetable Print


Adcock, Colin. Selecting Commercial Vegetable Varieties in Florida.  Quincy: UF/IFAS Panhandle Agriculture Webpage,  Volume: 1 Issue: 4.  Fall 2009

Bonina, Jennifer and Cantliffe,   Daniel J.  Seed Production and Seed Sources of Organic Vegetables. [HS-981]  Gainesville: UF/IFAS Cooperative Extension Service, November 2009 http://edis.ifas.ufl.edu/hs227   

"F1 hybrids" [On-line article.]  London: Royal Horticultural Society, 2011. http://apps.rhs.org.uk/advicesearch/Profile.aspx?pid=710

Kelley, Terry (UGa Extension).Heirloom Tomatoes: New Life For Old Varieties.”  In: Green Garden News. UF/IFAS Santa Rosa County Extension Service, May 2006. http://santarosa.ifas.ufl.edu/documents/may06.pdf  p.3 

Scalera, Sally.   Heirloom Vegetables [FS 6045 HORT].  Cocoa: Brevard Co. Extension Service, March 2006.  http://brevard.ifas.ufl.edu/Forms%20and%20Publications/PDF/Heirloom%20Vegetables.pdf  

Stephens, J.M. et.al.  Florida Vegetable Gardening Guide [SP103].  Gainesville: UF/IFAS Florida Cooperative Extension Service, February 2009,  http://edis.ifas.ufl.edu/vh021

Treadwell, Danielle. Old-time vegetables offer new opportunities to Florida farmers, UF experts say . Gainesville: UF/IFAS News, January 21, 2010  http://news.ifas.ufl.edu/2010/01/21/old-time-vegetables-offer-new-opportunities-to-florida-farmers-uf-experts-say/

Watson, Benjamin.  Taylor’s Guide to Heirloom Vegetables . Houghton Mifflin Harcourt, 1996.  In:  Vavrina,  Charles S., Armbrester Karen and Pena, Michiko.   Growing Heirloom Tomato Varieties in Southwest Florida. [HS-921] . Immokalee: UF/IFAS SWFREC, April 2003.  http://edis.ifas.ufl.edu/hs174  


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.  Millie Ferrer-Chancy, Interim Dean. Last update: 06/28/2011.  This page is maintained by Dan Culbert