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Mar 15

Spotlight Edible of the Day: Cool Season Crops – Nutritional Powerhouse Plants: GREENS

Posted by GeriMiller on 15 Mar 2011. Filed under  Cool Season Crops, Garden Care, How To Guides, Spotlight View Comments


“I have no truck* with spinach, kale, and similar chlorophyll. Any dietitian will tell you that a running foot of apple strudel contains four times the vitamins of a bushel of greens.”

S.J. Perelman     *Old English phrase meaning refusing to have anything to do with them.


Oh, if it were so! I know that it’s likely that you’ve dashed your nutritional New Year’s Resolutions to bits by now so I felt compelled to sing the praises of these ‘gentle giants’ of the cool season garden just so you’re armed with the “411” when you regain your nutritional sanity in time for spring and summer! So… here we go.

NUTRITIONAL NEWS FLASH! New Harvard study reveals “a strong association between adults’ levels of optimism and the amount of carotenoid antioxidants in their blood. Carotenoids are found in richly colored green and orange vegetables, including kale, sweet potatoes, carrots, and collard greens. The more servings of carotenoid-containing vegetables you eat, the results suggest, the brighter your outlook.” Got the Blues, Eat More Kale by Tim Philpott, Mother Jones.


Spinach • Turnips • Collards • Kale • Mustards • Beets • Swiss Chard


Lately, these beautiful plants have found their way from the pages of regional home-style cookbooks onto the menus of culinary star restaurants everywhere. They even made the January cover of Bon Appetit! At mar’sel restaurant at Terranea Resort, one of my restaurant gardens, Chef Fiorelli uses the baby leaves (micro greens) of the Bull’s Blood beet in his culinary creations.

Chef Fiorelli’s hearts of palm, avocado w/ yogurt lemon and dill w/ Bull’s Blood micro greens


I’ve been happy to see that my clients do not resist when I include them on their planting lists. Quickly they realize that these greens are not difficult to grow AND possess the added bonus of bringing gorgeous color and texture into an otherwise drab winter garden.

Nutritionally, you can’t beat greens. They are high in Vitamin A, Vitamin K, folic acid, dietary fiber, antioxidants, carotenoid, riboflavin and iron, as well as a great source of fiber, and a good source of omega-3 fatty acids. The darker and leafier the green, the higher the health benefit for us – anti-aging, cancer preventing, skin care, pregnancy health, heart health – to name a few.  Convinced? Good…now let’s get out in the garden and grow them!






  • Latin name: Spinacia oleracea
  • Family: Chenopodiaceae


  • Latin name: Brassica rapa var. rapa “turnip greens” (“turnip tops” in the UK) are similar to mustard greens in flavor.
  • Family: Brassicaceae


  • Latin name: Brassica oleracea L.
  • Family: Brassicaceae



  • Latin name: Brassica Juncea
  • Family: Brassicaceae


  • Latin name: Beta vulgaris L. subsp. vulgaris
  • Family: Chenopodiaceae

Swiss Chard

  • Latin name: Beta vulgaris L. subsp. cicla.
  • Family: Chenopodiaceae





Searchable database on varieties from Cornell University.





Climatic Requirements:

Most greens prefer the cool weather of early spring and fall (60° to 70°F). Kale and collards are tolerant of hot summer weather. Mustard greens bolt quickly in summer and may be better as a fall crop. Rapid, succulent growth is desirable, so supply plenty of moisture and fertilizer.   Most greens are frost-tolerant and may even taste better after cold weather sets in. In many areas, kale and collards will grow all through the winter if slightly protected.  Kale can withstand temperatures in the upper teens; however, the other greens can withstand medium frosts.  LIGHT: sunny, tolerates partial shade




Soil Requirements:

Leafy greens grow best in well-drained soils, rich in organic matter. Loams generally produce the greatest yields of leafy greens; however, sandy loams are better for overwintering and spring crops. A soil pH of 6.0 to 6.5 is optimum. Leafy greens require quick, continuous growth to achieve the best quality.




Cultural Practices:


A steady supply of water is important for good plant growth and quality. Insufficient moisture may result in tip burn, slow growth, and less flavorful leaves.  Avoid wetting the plant when applying water in order to avoid disease. If possible, irrigate with drip lines, or soaker hoses. If using overhead (sprinkler) irrigation, do it in the morning so the plants dry quickly as the day warms.

Weed control

Weed control is important. Hand pulling is recommended in lieu of using herbicides. Cultivate lightly as these plants tend to be shorter rooting. Applying organic material as mulch can provide a temporary weed barrier adding nutrients to the soil as it degrades.

Planting Requirements and Propagation







Swiss Chard



Cornell University Cooperative Extension, “Fertilizing Garden Soil”

Greens are medium to heavy feeders; sidedress when plants are 4 to 6 inches tall with a all purpose organic fertilizer.  Additional side dressings of an organic nitrogen source especially in sandy soil may be needed.

I stress that just by adding organic matter such as well-rotted manure or compost to the soil before planting and seasonally you will increase the level of nutrients, improve soil microbial activity, and increase water-holding and nutrient-holding capacity. Organic matter also improves the physical condition or texture of the soil for cultivation and improves soil structure so the surface of the soil does not crust. Any soil can be/should be improved through the addition of organic matter. As HGEL has often advised, cover crops are also an important, inexpensive way to add organic matter to the soil, and much of plants nitrogen needs can be met via cover cropping.  Before applying amendment or fertilizer it is always a good idea to do a soil test so that you know exactly what is in or isn’t in your soil. Contact your local County Extension office for information on soil testing. Fertilizer may be either broadcast and worked into the soil before planting time or side dressed two inches to the side and three inches below the seed at the time of planting.

The Quick and Easy Guide to Organic Fertilizers – Cornell University Cooperative Extension

How to convert an Inorganic Fertilizer Recommendation to an Organic (Univ. of Georgia)




Pest/Disease Control:

Pests & Disease

INSECTS: flea beetle, cutworm, cabbage root maggot and fly, imported cabbageworm, cabbage looper worm, aphid, harlequin bug

DISEASES: blackleg and black rot, clubroot, yellows

In an organic system pest and disease management is based on prevention. The goal is to have a healthy, balanced plant and soil system in which pest populations will be stay within tolerable limits. In a conventional system, synthetic pesticides may help a grower save the current crop from an immediate pest problem; however, in many cases, the problem recurs or another develops AND the cumulative effect of using synthetic fertilizers or pesticides is damaging to the environment, humans and animals. The organic approach is based on the theory that major pest problems usually occur when something is out of balance in the system. These are questions organic gardeners should ask themselves when things seem to be going wrong:

-Are the plants undernourished or stressed from growing too quickly?

-Is there a nutrient imbalance?

-Is the soil too wet or too dry?

-Has a good crop rotation been followed?

-Is there a diversity of plants to support beneficial insects?

Studying the problem and trying to determine why it occurred should help prevent similar problems in the future. This will, of course, take time to learn and develop. Unless gardeners refuse to use any pesticides, they may at times choose to apply some organic pesticides to save a specific crop.

A Word about the Integrated Pest Management (IPM) approach

This is system is well-suited for organic production and one, as a Master Gardener, I always recommend. IPM is a system in which insects, diseases, and weeds are closely monitored, and different methods are used to keep pest populations at levels that are not economically damaging with minimal adverse environmental effects. IPM encompasses use of cultural and biological control methods, use of resistant varieties, and a VERY judicious use of pesticides. HGEL recommends that, In the event pesticides must be used, select ORGANIC ones with low toxicity, non-persistent residues, narrow spectrum of control, and low environmental impact.

A Resource Guide for Organic Pest and Disease Management (Cornell Univ.)

There are four regional IPM centers in the U.S. – North Central, Northeastern, Southern and Western.

Here is a link to a searchable database to find the IPM sites in your region:

There is no guarantee that once an organic system is established there will never be a disease, weed, or insect problem. Stressful conditions that a gardener cannot control will occur, such as weeks of endless rains, droughts, periods of extremely high temperatures, hurricanes, plagues of grasshoppers, or hail. Likewise, if an airborne disease invades your area, your plants will probably be infected. However, with careful observation and preparation, an organic system should progressively have fewer pest problems as years go by.





All green parts are edible, and may be harvested at any time. Seed can be sown somewhat thickly and the thinnings may be good in salads. Mustard, kale and collards may have their larger leaves harvested. New leaves will provide a continuous harvest until leaves become tough or flavor strong.


Cool (32°F), moist (95% relative humidity) conditions; 10 to 14 days


Cool, moist storage best (may be canned)


Favorite Recipes

Swiss Chard



Beet Greens

Collards Greens

Mustard Greens

Turnip Greens

GRIST TV: DIY HEALTHY JUNK FOOD – “How to Make Kale Chips” video

2 Responses to “Spotlight Edible of the Day: Cool Season Crops – Nutritional Powerhouse Plants: GREENS”

  1. This is a terrific posting and I appreciate whoever to took the tim to compile and post it! Thank you!

    Posted by Chris on September 12th, 2012 at 3:24 am Reply

    • So glad that you enjoyed it, Chris! Hope you stay tune to GroEdibles blog for more!

      Posted by GeriMiller on September 12th, 2012 at 6:58 am Reply

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