Growing Greens

Leafy Green Production

No other vegetable packs a nutritive punch quite like leafy greens, which include Swiss chard, kale, collards, lettuces, arugula, spinach, Asian greens and mustard. Mesclun, which is French for mixture, is available in most seed catalogs. It usually consists of a mix of lettuces and other tender greens. These vitamin and mineral-packed vegetables can be enjoyed cooked, sautéed, as salads or in soups. These plants are easy to grow in West Virginia and if done right, you can enjoy leafy greens all year round.

Soils and Fertilization

Good soil preparation will help you reap what you sow. Choose a location for the garden that gets at least six to eight hours of daily sun. Prepare the seedbed by tilling to a depth of at least three inches, getting the soil fluffy and weed free. Greens prefer well-drained soils and can tolerate a wide variety of soil textures.

The ideal pH for these plants ranges from 5.5 to 6.8. If soil tests indicate acidic soils, ground limestone rock, or lime, should be added as a soil amendment before planting. Follow your soil test recommendations for any amendments or use one pound of 5-20-20 per 100 square feet. Broadcast the fertilizer and incorporate it into the soil, then surface apply an additional pound. This will usually be the only fertilizer applied until steady leaf production occurs. Additional nitrogen will be needed for steady leaf production.

Planting

Leafy greens can be sown directly into the ground or by using transplants. If starting seeds indoors as transplants, they will need to acclimate to the outdoor environment before planting directly into the ground. One week prior to planting, place transplants outdoors in a safe location for a few hours. Each day gradually increase the amount of time transplants spend outdoors. After several days, transplants should be spending 24 hours outdoors and will be ready to be planted into the ground. Greens make wonderful garden plants in the early spring or late fall.

Typical spacing for greens is 8 to 12 inches apart in 18- to 24-inch rows, so you have one to two plants per square foot. Plants that are direct-seeded should be thinned to these specifications. Sow every two to three weeks to have a continuous supply of lettuce or other leafy greens.

Planting Schedule

*Planting Schedules for Open-Field, Low Tunnel and High Tunnel Vegetable Crops in West Virginia, Lewis Jett.

Varieties Recommended for West Virginia

Mulching & Weed Control

All types of greens will benefit from being mulched. Be sure to keep the bed weed-free, especially when seedlings are young. When greens reach maturity, a layer of straw or fabric mulch will help reduce weed growth and retain soil moisture and heat. When hand-weeding young greens and lettuce, care should be taken as they are shallow-rooted.

Insects & Diseases

Strategies for Disease/Insect Management

The easiest approach to disease and insect management is understanding the pest or pathogen. Using an integrated pest management (IPM) approach refers to the use of multiple strategies to achieve crop management results with the use of pesticides only when necessary. This will alleviate the need for just one control measure and yield better results. Some strategies that should be considered part of the IPM process are:

1. Crop Rotation: Some insects and pathogens that cause foliar disease overwinter on crop residues and in soils. When damaging levels are reached, a rotation to a different family of crops, such as corn or another summer grass species, for at least two years is effective.

2. Site selection and preparation: Sites should be well-drained, and if there isn’t a well-drained area, one can be created by forming raised beds. Correcting any nutrient deficiencies and soil pH should be done before planting. Maintaining proper records of soil amendment applications and pest or disease problems is essential.

3. Seed Health: Choosing certified seeds from a reputable source will ensure you aren’t introducing any diseases that may affect your harvest.

4. Sanitation: Pathogens can be spread by equipment and workers, so cleaning off these will minimize the spread of any infections. Crops should not be worked under wet conditions.

5. Irrigation: Care should be taken not to wet foliage. Irrigation should be done early in the day, so if the foliage gets wet, it can dry rapidly.

6. Weed Control: Weeds in and around fields and gardens can be hosts for insects and diseases. Proper weed management in these areas will decrease the risk of insects and diseases in your garden.

7. Scouting: Plants should be monitored throughout the season so that if a problem arises, action can begin promptly. Set action thresholds, or the point at which chemical action will be necessary, so you have a consistent measure to begin using chemicals.

8. Chemical control: This option should only be used when all other options are exhausted. Understanding chemical properties and reading labels will be highly beneficial. Fungicides are effective at controlling fungi, while copper compounds can be used for both fungi and bacterial issues. Monitor the weather and when needed, fungicides should be applied before it rains, not after. Sprays should be applied according to label instructions. Seed treatments are those used to help with soil-borne diseases, such as damping-off.

9. Beneficial Insects: The growing environment can be manipulated to attract beneficial insects, or these insects can be introduced by purchasing. Lacewings and lady beetles are very effective for pest control and pollination when populations are sufficient.

Bolting

Bolting refers to premature seed or flower stalk production before the harvest of the vegetable, and it typically renders the crop unusable. Bolting occurs in members of the Brassicaceae family when the weather is warm for long spells. High temperatures and increased day length can cause plants to bolt. Greens can be planted earlier in spring or later in the fall to avoid this condition.

Harvesting

Leaves should be harvested at the desired size. Leaf yellowing or browning is a sign that the plant is over-mature and should be removed. Over-mature greens will be bitter, tough and stringy. It is best to harvest greens in the cool of the morning and process or refrigerate them as soon as possible. Remove any soil from the leaves by running cool water over them. Remove all moisture before use. Older leaves can be cooked while young leaves are great in salads.

A continuous harvest can be done by sowing an area thickly with a mixture of your favorite greens. When leaves are roughly 6-10 inches tall, shear them down to the crown with sharp scissors. They will regrow quickly if watered and fertilized and be ready for another harvest in a few weeks.

Preparing

To wash fresh greens, remove stems or heavy ribs, place leaves in cold water and let soak for a few minutes to loosen grit or dirt. Repeat the process two or three times and let drain or dry in a salad spinner.

To steam greens, cover them in a basket over boiling water for about five minutes Depending on plant maturity, some greens may need more than five minutes. Greens can also be cooked in a covered container in the microwave with a small amount of water for approximately five minutes. Cook greens just until tender to retain the most nutrients.

Storing

Unwashed, leafy greens vary in how long they will stay fresh when refrigerated. Spinach, kale and arugula will stay fresh for up to one week in a refrigerator, while a head of lettuce and swiss chard can stay fresh for up to two weeks.

Preserving

Most leafy greens lend themselves well to all types of preservation – canning, freezing and drying. Freezing greens is the preferred method of preservation, as it can be done with any amount of product. Water blanch collards for three minutes and all other greens for two minutes. Cool, drain, package the greens leaving half an inch of headspace, seal and freeze. Frozen greens are ideal for casseroles, soups and other cooked recipes.

Canning spinach and other greens such as chard is a good option for those that have bushels of greens at once. Canning greens requires a pressure canner and about four pounds of greens per quart, or two pounds of greens per pint. Safely canning a load of greens in a pressure canner will also take 70-90 minutes at the proper pressure, depending on the size of the jar, not including heat-up and cool-down times.

Drying greens can be great for those interested in a quick, shelf-stable snack (think kale chips) or for a quick add-in to soups or slow cooker meals. Greens can be safely dried in an oven or food dehydrator by using the right combination of warm temperatures, low humidity and air current.

Nutrition

Dark green leafy greens are packed with many nutrients, including antioxidants, fiber, folate, magnesium, calcium, iron, potassium and vitamins A, C and K. Some greens, such as mustard, are also rich in many of the B vitamins. Greens are also very low in calories, carbohydrates, sodium and cholesterol. Because of their significant amount of folate, greens promote heart health, help prevent certain birth defects and can protect against the development of some cancers.

Resources

• Refer to Understanding Your Seed Catalog for information on ordering seeds.
• Refer to Using Transplants in the Garden for tips on growing with transplants.

References

How to Grow Greens. Michigan State University Extension. 2016.  https://www.canr.msu.edu/resources/how_to_grow_greens

CABBAGE, BROCCOLI & OTHER COLE CROP INSECT PESTS, 2022.  https://hgic.clemson.edu/factsheet/cabbage-broccoli-other-cole-crop-insect-pests/

FoodKeeper App  https://www.foodsafety.gov/keep-food-safe/foodkeeper-app

Selecting, Preparing, and Canning Vegetables Spinach and Other Greens. 2018  https://nchfp.uga.edu/how/can_04/spinach_greens.html

Freezing Greens (Including Spinach), 2014.  https://nchfp.uga.edu/how/freeze/greens.html

Preserving Food: Drying Fruits and Vegetables  https://nchfp.uga.edu/publications/uga/uga_dry_fruit.pdf

Dark green leafy vegetables, 2016.  https://www.ars.usda.gov/plains-area/gfnd/gfhnrc/docs/news-2013/dark-green-leafy-vegetables/

Damicone, John. Diseases of Leafy Crucifer Vegetables (collards, kale, mustard, turnips), 2017.

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