University of Vermont Extension 
Department of Plant and Soil Science

Spring News Article
line
GARDEN “KEEPER” CROPS

Dr. Leonard Perry, Extension Professor
University of Vermont 

Beets, carrots, and potatoes are some of the garden crops that keep for long periods in storage.  Now is the time to plan for such “keeper” crops in this season’s garden, and to sow several, in order to be enjoying them right through to this time next year.
           
Before planning what to sow and grow, you need to plan if you have the right storage conditions.  Ideally you would need three types of storage environments for longest storage, although you can often get by for shorter periods with less than ideal.  Even if you don’t have the right storage to keep crops for long periods, you can always enjoy them fresh and freeze, or otherwise preserve others.  A range of storage months is given, as best storage will vary with conditions and the fruit quality, and might even be longer if you get it just right, or with just some loss of quality.
           
Those vegetables that store longest in “warm” (55 to 60 degrees F), dry, and dark include sweet potato (4 to 6 months), winter squash (2 to 6 months), and pumpkins (2 to 3 months).  You might find such conditions in hallway closets or basements, perhaps in a garage.
           
Another group prefers “cool” (35 to 45 degrees F), dry and dark.  These include garlic, onions, and shallots and all store generally for 6 to 8 months.  Look for these conditions in an unheated garage or basements in older homes, or outdoor storage buildings.  I have one of the latter, with minimal heat from a space heater to keep conditions just right.  Of course you could build an outdoor storage structure during this growing season, a simple one being a buried container which you cover with a foot or more of straw during the winter.
             
Most keeper vegetables prefer cool (35 to 45 degrees F), humid, and dark.  Best is on the lower end of the range, except for potatoes which prefer 40 to 45 degrees.  Good keepers in cool and moist include beets (3 to 5 months), late cabbage (3 to 4 months), carrots (4 to 5 months), celeriac (3 to 4 months), parsnips (2 to 6 months), potatoes (4 to 9 months), winter radishes (2 to 4 months), and rutabaga (2 to 4 months). 
           
You can keep the humidity up around roots crops by burying in moist sand or compost (if loose and lightweight or sandy) in open baskets or similar. Some recommend sawdust, but it can absorb moisture away from the vegetables, drying them out.  Plastic-lined boxes work, as long as left open for air circulation and the medium isn’t too wet.  A plastic bag with a few 1/4-inch holes for air exchange, in a spare refrigerator, works for small quantities. 
           
You also should consider your space for growing crops to keep for storage.  For small gardens, consider crops that don’t take up much room like beets, carrots, celeriac, garlic, parsnips, and shallots.  If you have plenty of room, consider cabbage (a bit difficult for novice growers), onions, potatoes, pumpkins, rutabagas, sweet potatoes, turnips, and winter squash.  Or, in a small space you can grow just a few of these as with a small raised bed of onions, a grow-bag of potatoes, or bush forms of sweet potatoes. 
           
Once you figure what you like to eat, have room for in your garden, and can store properly, figure how many you want and when to start them.  You’ll find instructions on seed packets if sowing your own, or in catalogs.  Those to sow indoors in containers in April for planting out after the last frost include celeriac, onions and shallots.  Those to sow indoors in May include winter squash, pumpkins, and cabbage.  Or you can sow the squash and pumpkins directly in the garden one week after the last frost date.
           
One to two weeks before the date of usual last spring frost plant potato “sets” (small plant parts you buy just for growing) and those of onions and shallots.  Sow seeds then of rutabaga and parsnips.  Although you sow carrots, beets, and turnips in spring for summer harvest, for storing, mark your calendar to sow these 10 to 12 weeks before the first fall frost date.  After this date in October is when most plant garlic sets, to harvest the following summer.
          
If you’re not familiar with spring and fall frost dates for your area, you might contact your local weather service office or independent garden store.  Of course you can find them online from the National Climatic Data Center, along with all kinds of other weather data.  Go to their website (www.ncdc.noaa.gov) and search for “frost dates” or “climate normals”.  Keep in mind that these are only “averages” and will vary from year to year, and are often affected by microclimates.  Low pockets in yards and valleys often stay colder in spring, while areas near bodies of water often warm up sooner. 
           
Although it’s hard to think about next winter now, just as this one is ending, you’ll be glad you did when it arrives and you have months of vegetable crops to keep in storage.  It’s special to cook these for yourself or guests, knowing such food came right from your own garden.  You’ll eat healthy, and save on grocery expenses too.

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