Michelle Grabowski
Annie Klodd
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Extension Educator Annie Klodd browses peppers in the 2018 Rupp seed catalog |
For many gardeners, the first sign of spring arrives in the form of seed catalogs in the middle of winter. Glossy color pages provide the promise of flowers, fruits, and vegetables in the coming season. Seed catalogs can open up a wide array of possibilities not to be found in local garden centers. Savvy gardeners can choose from multiple colors of flowers or vegetables, find disease resistant plants or varieties especially well-suited to their growing conditions.
To make the most of what seed catalogs offer, it is important to understand the terms, abbreviations, and numbers that can be found in the description of each variety.
Growing Requirements and Varieties
A hybrid tomato variety displaying days to maturity and disease resistance codes in the 2018 Johnny's Seed catalog |
Days to Maturity depends on variety. For example, the Racer Plus pumpkin in the Johnny’s catalog matures in about 85 days, while the Cargo PMR variety takes about 100 days (see photos below). In Minnesota, we garden in a relatively short growing season.
When planting a crop with a long maturation time, like pumpkins or winter squash, you may prefer a variety with a shorter DTM. The DTM is approximate, and the exact number of days it takes a crop to mature is also affected by things like weather and soil quality.
F1: This means the variety is
a hybrid. Hybrids are bred from crossing two other varieties together in order
to get certain desirable traits of both parent varieties. Examples of desirable
traits include flavor, color, and disease resistance. We do not recommend
saving seeds from hybrids in your garden, because they are usually sterile or
will not produce a crop true to the parent plant.
Open Pollinated (OP): If a
variety does not say “F1,” it may instead say Open Pollinated or “OP.” This
variety is not a hybrid. It can reproduce by itself and its traits remain
consistent from one generation of seeds to the next. The Yankee red bell pepper
is open pollinated, while the Red Knight red bell pepper is a hybrid (photos
below). If you would like to save seeds from your crop, we recommend selecting
open pollinated varieties.
Lettuce varieties displaying OG and conventional options, and pelleted options. |
Determinate and indeterminate:
Some vegetables have varieties of two different growth habits: determinate and
indeterminate, and gardeners can choose based on their needs. Tomatoes are a great example of this. Determinate varieties grow to a certain size and then
produce all their flowers at once, so the whole crop ripens around the same
time. Indeterminate varieties continue to flower and ripen throughout much of
the season. These words may appear either in the
variety description or with a symbol.
Disease Resistance
Resistance codes for tomatoes listed in the 2018 Johnny's Seed catalog. |
Look for letter codes listed after the variety name. You may see (F, V, TMV) after the name of a tomato variety. Each letter indicates a disease that this variety is resistant to.
Seed companies do not all use the same letters to represent different diseases so check the catalog for a key to find out what each letter stands for. If no letters are present after the variety’s name, that variety is not known to be resistant to common diseases.
It is important to know what
diseases are present in your garden or in Minnesota when choosing resistant
varieties. Some diseases are common only on farms or in other regions of the
USA and resistance to these diseases is not an important factor in a Minnesota
home garden. The online diagnostic tool, What’s wrong with
my plant? can help gardeners identify disease problems they have
encountered in previous seasons.
High resistance: Very minor
or no symptoms of disease will be observed during the growing season.
Partial, low, or moderate resistance
or disease tolerant: Symptoms of disease may appear but the plant will
be able to reduce the damage done by the pathogen and will often produce a good
crop.
Seed Treatments
Treated seed: seed that has
been coated with a fungicide or insecticide to protect the seedling from insect
pests or diseases. Fungicide seed treatments only protect the seedling from damping
off and do not last through the growing season. Treated seed is not
necessary for transplants started indoors because gardeners can easily prevent
damping off by using clean materials and keeping the potting mix at the right
temperature and moisture for optimum seedling growth.
Pelleted seed is seed coated
with a hard covering often made of clay or other material. Pelleting is often
done to small seeds like lettuce to make them easier to handle. This type of
seed coat does not contain pesticides.