Clover Gets Overtime in the Urban Home Garden
Cover crops are any crop grown to enrich and protect the soil. We typically do this when our plots would otherwise be empty. This past fall, I seeded crimson clover in what will be, this spring, our main herb, and vegetable bed—and now it is time to act. All winter long, the clover has been soaking up the excessive rains we had—their extensive root systems also kept precious soil from eroding. This was especially important to me since this particular plot happens to drop nearly a foot in seventy feet, north-to-south. Also in its arsenal, is this legume's ability to "fix" nitrogen into the soil—taking atmospheric nitrogen and converting it to a plant-friendly form with the help of mutually beneficial bacteria in its roots. This translates to less store-bought nitrogen fertilizer for the farmer—from 50-150 pounds of nitrogen fixed per acre! One-quarter of an ounce of seeds covers approximately 75 square feet. I used about two ounces in my area, and the result was a beautiful, green mat of clover, nearly knee-high by spring, and starting now to bloom crimson red.

How do you do it exactly? You sow about six weeks before the last frost date—just broadcast the seeds as evenly as you can, rake the soil to cover them, and water them in. It generally takes 2-3 days to sprout if the days are still warm and 7-10 days if the days are cooler.

Now is the time to begin to prepare our garden beds. When you are dealing with cover crops, now is the time to cut them down and process them. So do you weed-whack them down, till them in, and start planting? You could do this, but a large portion of that precious nitrogen I mentioned may be tied up for a few weeks as the clover decays. In the Urban Garden, I whacked it down to the ground and raked the vegetation into a long, narrow row along the edge of the plot to rot a little. This exposed the ground and let it dry out quite a bit before I would till it. I took a hard rake (a hoe would work, too) and broke the surface tension in the soil—this aided in the drying process. It may be a good idea to check the weather to make sure a heavy rain is not coming—if you have no choice and have to cut the cover down, wait to rough up the surface until after the rain.

After the soil is dried out, you should test your soil before going any further. Big box stores offer soil test kits that work well enough. After having grown 16 watermelon plants in this plot last summer, my test revealed a slight nitrogen deficiency. I knew the clover would help this in time, but I like to be sure. So, after I had raked the clover greens back on the plot evenly, I spread two inches of composted cow manure and two inches of pine fines on top of the greens. For added assurance, I added, as per the label, a balanced organic fertilizer complete with a mycorrhizal inoculant. I tilled all of this under—tilling, and watching the color of the soil change from brown to almost black with bits of clover throughout. I am making rows for tomatoes, peppers, and eggplant, in this plot. So after I tilled, I constructed these rows with a hard rake, breaking up any large clumps as I went. To get my rows straight—an obsession of mine—I used string and stakes to provide me a reference line. I mulched between the rows with a layer of newspaper covered with partially rotted straw. 

So, what about containers and raised beds? Can you use cover crops in these areas? Will this work if you do not like to till/believe in tilling? The answer to these questions is: Yes!

The treatment of both large year-round containers and raised beds is the same. Sow your seeds the same way in the fall. The only thing that changes is that you may need to water them throughout the fall—as containers seem to dry out much faster than in-ground beds. When it comes time to deal with your cover crop, you can address it several ways—I will supply you with a few methods here. Firstly, and most simply, you can pull out the clumps of clover, compost them in a pile, and add them back as a top dressing throughout the season. The only deal here is you have to wait. You could also chop them and leave them on the surface to decay, becoming mulch in time. Lastly, you could pull the plants, chop them, let them rot a bit where they fall and then work them into the top few inches of soil with your hands.

Whatever means you have, and regardless of the type of garden you are currently growing in, cover crops can help improve your soil and thus your yield. You could use Crimson Clover as I have, Hairy Vetch, or Winter Peas—there are several other cover crops. Pull them out and compost them, let them bloom, chop them up, and till them under.

By Blair Combest MBG horticulturist

Food for Thought
As usual (maybe there’s some reason I like Herbs do you think?) my thoughts are on food. Once again my thoughts are also on thrift. The pandemic has created major issues in food production, packaging and movement from one place to the other. This horrible virus has made us notice just how dependent we are on food coming from somewhere else to here- here being home. I went to the grocery store the other day, and I was appalled at what was not on the shelves. People have gone frantic for the simplest items-even to the extent of hoarding. The empty shelves made me think about inexpensive variations that could help in this situation. Thinking about plants that we now have or have had before for sale at the Memphis Botanic Garden, I thought of mint. Stop groaning! I know you are saying, “But, mint takes OVER!” Take a breath: sometimes being an opportunistic grower is a good thing!

Whenever you have a plant that will increase readily: USE IT! In the case of edible plants: EAT THEM (or share them, make tea, or harvest them and prepare them for later use). Mint could be used to make simple syrups.  Mint is a purported nervine: calming stress and anxiety makes it a great plant for the current days. You can make pestos with mint. Get that look off your face: you can make sweet pestos! Instead of using olive oil you could use walnut, sunflower, pecan, macadamia, or other nut oil. Omit the cheese. Add a little sugar or sugar substitute if you wish something sweeter - or serve it with sugar cookies, teacakes, shortbread, WHATEVER! Have ready-made cookies in your refrigerator or freezer? Bake a batch (or make some from scratch!). Your house will smell lovely and then serve the cookies with the sweet pesto. Make the pesto with just the oil and herbs, place in a freezer container, label the container with the date and contents, and you have just made a paste. Pastes are an excellent way to preserve herbs: the oil coats the herbs and keeps them a more pleasant green by keeping them from oxidizing. These pastes taste lovely and fresh once thawed.
Use the herbs and make simple syrups. Use simple syrups in place of wherever you normally use sugar: in your coffee, teas, or to replace sugar when baking. Check for conversion information online -you have to pay attention to the fact that you will be using a liquid instead of a dry sugar and you will have to adjust the moisture ratio by reducing other liquid in the baked good. Drizzle the simple syrup over one of your homemade cakes. You could also make spritzers/faux soda by using the simple syrup along with a seltzer water or sparkling water. Add an herbal infusion or tea to make the flavor stronger. Raid your cabinets and see what extracts you have hiding out: a little splash of those can add a crazy flavor punch to your faux soda.

Make a shrub. A shrub is a vinegar that’s been infused with herbs, spices, fruits, and other flavorings. Shrubs are often sweetened with honey and then diluted with a touch of sparkling water (or sparkling wine!), or wine, or flat water, or not diluted at all and sipped. Shrubs are drinks that were created to preserve fruit harvests and are amazingly refreshing on hot days, or when you’ve been working very hard. Trust me: give shrubs a try!

Herbs are an inexpensive way to flavor your bottled water, or the water in your workout bottle or Thermos. Flavoring your water is as simple as taking a few sprigs: 4-6 inch long of whatever edible herb that you like, then crush or otherwise bruise it, then drop it into your water. Voila! Instant flavored water: fresh, no sugar added, no crazy unpronounceable ingredients, flavored water of your way.  
What herbs are good to use these recipes? Mint of any kind: ginger, peppermint, spearmint, chocolate mint, apple mint, generic we-don’t-know who-it-is-mint, whatever. Other herbs: thyme, lemon thyme, lemon verbena, lavender, oregano, tarragon, Texas tarragon ( Tagetes lucida ), sage, rosemary…pretty much any culinary herb that you like!

Let’s begin to end our dependence on the marketing of food and grow our own: maybe not everything but baby steps. We can start in little ways: begin by growing some herbs. If you are lucky and they grow well for you then share these herbs with others. Don’t be unhappy that you have a lot of something. Be happy to share with someone that doesn’t…
-2 teaspoons fresh herbs (or 1 teaspoon dried)
-Water heated just to boiling

  • Pour some of the boiling water into your ceramic or enamel teapot or cup to warm it.
  • Empty out the water and add herbs for each cup of tea (if using a teapot, add one more spoonful on top of the one per cup).
  • Steep for 5 minutes

Herb teas don’t brew up as dark as regular teas do so give them a taste test: Add more herbs if it tea is too weak, but don’t increase the steeping time as this can give the tea an unpleasant grassy taste.
If using fresh herbs, after drinking your pot of tea, add one-third of the water you did in the first steeping and end up with a respectable second cup or pot.

Herbal Syrup (Yield 2 cups)
-1½ cups water
-1½ cups raw, organic sugar or cane sugar
(Note: Raw sugar will cause the syrup to be more golden brown than cane sugar. Honey or maple syrup can be used, but will alter the flavor of the syrup and may have a dominating flavor. Stevia leaves can be infused with the other herbs, but will not thicken like sugar, the result is like a thin tea.)
-About 8-10 herb sprigs or a large handful of leaves

  • Combine water and sugar in a small saucepan
  • Place over moderate heat and bring to a boil
  • Stir to dissolve sugar
  • Remove from heat and add the herb leaves, bruising them gently against the side of the pan with a spoon
  • Cover and let sit for at least 30 minutes or to room temperature
  • Remove the leaves, squeezing them to extract all of the herbal essence into the syrup
  • Pour into a clean bottle or canning jar and label them

The resulting syrup will keep in the refrigerator for about 10 days, in freezer for 8 – 9 months, or until the next harvest season.
My Friend Carol’s Pesto: (Tweak this like I said above to make a sweet pesto. Any edible herb can be used in place of the basil. I like to use sage and toasted walnuts.)
-2 cups fresh basil leaves
-1/2 c grated Parmesan cheese – or nutritional yeast – or omit the cheese. Reduce the oil if omitting it…
-1/2 extra virgin olive oil
-1/3 c pine nuts, walnuts, or pecans (can toast the nuts to add a lovely flavor variation)
-3 garlic cloves
-salt and pepper to taste

  • Combine basil and nuts in a food processor. Add garlic.
  • Slowly add olive oil in a constant stream while the food processor is on. Scrape down sides.
  • Add Parmesan cheese and pulse again.

Makes 1 cup. (If you need to process a lot of basil quickly, you can process the oil and basil and then place it in a freezer baggie, label, and freeze. Later, pull out, thaw, and add rest of ingredients: presto, you have pesto!)
Quick Cold-method Shrub:
  • Wash fruit.
  • Remove hulls and stems. Lightly crush (berries), peel, pit and slice (stone fruit).
  • Place in a nonreactive container such as glass or stainless steel. Cover fruit with sugar and add a few sprigs of herb of choice (about ¼ cup), cover and refrigerate 24-48 hours.
  • Stir at least once per day. Add vinegar, then strain out the fruit.

Shrub is ready to drink. A good ratio of fruit:sugar:vinegar is 1:1:1 (ex: 1 pound of fruit is usually about 2 cups of fruit, to that you would add 2 cups of sugar, and then 2 cups of vinegar) Refrigerate and use within a month.

Shrubs can be sipped as is, or mix approximately ¼ cup of shrub to 1 cup of chilled sparkling or still water (or wine, or champagne!). Use less! Not strong enough-add more! This is all about taste.

For each cocktail, shake 2 oz. shrub, 1½ oz. spirit of choice, and ½ oz. lemon juice in an ice-filled cocktail shaker until frosty. Strain into an ice-filled Collins glass; top with some reserved fruit.
If you have any questions, call Sherri at (901) 636-4134.

By Sherri Sherri McCalla, Herb Garden Curator at Memphis Botanic Garden

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