Each year we’re enamored by all the beautiful seed catalogs that come in the mail. Flipping through the pages of charming old heirlooms and stunning new varieties is one of the best ways to spend a winter day. But whether you’re new to gardening or an old hand, understanding all the nuances of seed catalogs can be a challenge and getting it right can make a vast difference in the productivity of your garden.
In today’s post, we’ll tackle how to ‘decode’ all of your seed catalogs so that you can select varieties with the disease resistance, climate requirements, and growing period that work well for your garden.
Find the Seed Companies Location
Purchasing seeds from companies that grow in your region is a great way to ensure you’re getting varieties that will thrive in your climate. Here in the Southeast, we often look for plants that will tolerate long, hot, humid summers, common pests like vine borers, fungal diseases like blight, and mild winters.
That said, growing seeds from outside your area isn’t a terrible idea, but there are some features to keep in mind. Therefore, it’s important to check the address on the catalog and find out where they grow their seed trial gardens.
When browsing northern catalogs, take sun requirements with a grain of salt. A variety that thrives in full sun in Maine might enjoy some afternoon shade in Georgia. Crops also tend to take much longer to mature in cool, northern summers, so the ‘days to harvest’ may differ from what it will be in a southern garden.
Many growers in the Northeast are doing breeding for disease resistance. You may find some interesting new varieties that are worth experimenting with in their catalogs. Cool season crops from the Northeast and the Pacific Northwest may also work well for growing in the Southeast’s mild winters.
Catalogs from California and the Southwest may also offer great heat-tolerant and drought-resistant crops that could be worth looking into, though they may not be as tolerant of our humidity. California catalogs are also a great source for Asian heirloom vegetables.
Understand Days to Maturity or Days to Harvest
Most gardeners know that days to maturity is a rough estimate of the number of days it takes a crop to mature enough to harvest. But there are some nuances to this number.
When talking about transplants, the days to maturity usually refers to the number of days to harvest from the time you plant the transplant out into the garden, not from the date you started it indoors. When direct sowing, it starts the day the seed goes into the soil.
Occasionally, seed packets and catalogs may specify whether the number is referring to direct sown seed or transplants.
It can also differ widely when you’re talking about greens. Is the days to maturity referring to full heads of lettuce or big bunches of chard, or is it talking about baby greens for salad? Sometimes, descriptions like ours for Barese Chard will specify: 25 days for baby greens/50 days for mature leaves.
Keep in mind that conditions will also affect days to maturity. Cool spring nights will make heat-loving crops like tomatoes grow more slowly. Dwindling day length in the fall can significantly slow down fall crops like lettuce. In fall, we recommend you add 14 days to the days to maturity time for any variety you’ll direct sow and 14 to 28 days for any variety you will be transplanting.
Learn more in our post, When to Plant a Fall Garden.
Look at Disease Resistance Keys
Disease resistance is a critical aspect of selecting the best varieties for your garden. These days, most catalogs show a variety’s disease resistance using codes and a key.
For example, in our seed catalog you’ll notice our flagship tomato, Radiator Charlie’s Mortgage Lifter says (vw, fw1). When you check the key, you’ll notice that this means it’s resistant to Verticillium wilt (vw) and Fusarium wilt, race 1 (fw1).
*Note: In heirloom tomatoes, the lack of disease resistance in the description doesn’t necessarily indicate a lack of resistance. Many heirloom tomatoes have not been extensively tested for disease tolerance either in the laboratory, or in extensive field trials.
Below are our disease resistance keys for tomatoes and cucumbers. Other catalogs may use different keys, so it’s important to check each one.
Tomatoes
Cucumbers
Other crops in our catalog also feature disease resistance information, though it’s just plainly in the description. For example, the Golden Bush Scallop Summer Squash description says, “Downy mildew resistant.”
Gardeners in the Southeast Should Focus on the Heat
If you grow in the Southeast and are shopping for summer crops, heat tolerance should be a major focus. Consider varieties that have phrases like drought-resistant, heat-tolerant, and good pollination in heat.
The long summer also means a short spring, so we need to carefully select our cool season crops. Look for keywords like short-season, early, bolt-resistant, and long holding.
Consider Gardening in the Shoulder Seasons
Particularly in the Deep South, it may be prudent to plan a break during the height of summer. Few crops truly thrive in intense heat. However, the long seasons usually make it possible to grow one crop in early summer and another in early fall.
For example, you can often get a crop of early maturing tomatoes like Djena Lee’s Golden Girl (64 days), Pink Ozark VF (65 days), or Rosella Purple (65 days) in early summer. Then start more seeds indoors in July and get another crop as the season cools down in early fall.
Understanding what to look for in seed catalogs can make a big difference if your garden. Decode your catalogs this season to find varieties that will work well in your climate, thrive against local disease pressure, and fit into your succession plan.
Most of this information was based on Ira Wallace’s Guide to Vegetable Gardening in the Southeast. Grab a copy today for month by month advice.
The Beginner Gardener
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