Weeds are plants growing where we might not want to see them but their presence speaks to us about our soil. In sustainable gardening, we use the weeds to improve soil and we learn which weeds are edible. My all time favorite reference for weed identification is Dean Green’s “Eat the Weeds” web site, www.eattheweeds.com. Another great reference on the subject is “Weeds, Control without Poison” by Charles Walters. In his book, Mr. Walters writes about what each weed can tell us in regards to the quality of the soil, how weeds can benefit the quality, and what amendments or changes are needed to prevent weeds. For example, some weeds enjoy compacted soil; to reduce their population, you can aerate the soil. Other weeds grow in excess when soil is too low in calcium; to reduce their population, add calcium.
A specific weed I like to see is chickweed that grows on my property prolifically this time of year. You may see it around December each year and if you pull a clump out, it will likely stick to your gloves. In the photo, you can see it’s growing among other plants. Known to be a helper for digestive and inflammation issues, it can be included in salads so pull it out and eat it if found growing someplace you don’t want it. The presence of chickweed means nature has come to help improve soil deficiencies in calcium and phosphorus. I suppose I could just add more nutrients and in some cases, I do. For the season though, I leave the chickweed to grow big and healthy during the cool months so when the heat returns, it dies leaving nutrients behind. I have also read that chickweed indicates a good quality organic soil but a deficiency in minerals; I find that it does tend towards those areas on our property. This year in particular, we saw an increase in caterpillars I attribute to the warm and humid weather conditions. Chickweed, attracts predatory wasps that help control caterpillars which is yet another benefit to leaving this helpful weed in place! If you don’t have an abundance of chickweed, you can actually buy chickweed seeds and plant them as companions in your vegetable and herb gardens.
When preparing a new planting area or raised bed, I never pull weeds out. I just cover them with card board, compost and/or mulch so their death returns all those nutrients back to the soil. I rarely pull weeds except in between applying compost and mulch or when they are growing in landscaped areas. If I need to remove weeds from a landscaped area, concrete pavers, walkways, etc., I use a home-made spray, pull them by hand, or burn them (carefully). My favorite weed killing spray is made by mixing a gallon of 5% acid store vinegar, about 20 drops each of orange and cinnamon essential oil, and a drop or two of regular (non anti-bacterial) old fashioned dish soap. What I think will be a hot, sunny, dry day and first thing in the morning, I spray the weeds. They are dead by noon and the yard smells delicious!
In gardening areas, I use mulching materials to reduce weeds. I pay attention to what pops up in spite of the mulch because it may tell me something I need to amend in the soil. When I’m working around my plants, I pull the very few that pop up. The mulch also creates a moisture area, helps build organic matter in the soil, and feeds the soil microbes. I like to use a blend of pine straw, lawn clippings, chemical free hay, and/or shredded pine bark for mulch in the garden and raised beds. Extra nitrogen is needed when mulch is used so take care to add some extra nitrogen before you apply the mulch. I’ve used organic fertilizers, Azomite, granite screenings, rock dust, Epsom salts, calcium, manure, alfalfa, dry molasses, and cottonseed meal as amendments both under and on top of newly applied mulches. So far, I like a blend of those to help provide both the extra nitrogen and food for the soil microbes.
One of the best ways to prevent weeds is to place other pleasing and useful plants all over the planting areas. For example, if I want to plant a fruit tree, I’ll organize the entire area, taking into consideration the future plant growth, compatibility, sunlight, moisture, soil quality, and value of the tree and plants I’m going to use. I recently planted a small citrus grove. Citrus enjoys a more acidic soil so the companion plants around the citrus also prefer that type of soil. I chose a sun loving coffee, some Brazilian red cloak to attract pollinators, some legume plants for nitrogen like cow pea, sudan grass, and pigeon pea, and I’m letting a sweet potato and Cuban oregano spread out in between to help keep weed control, retain moisture, and promote a biodynamic soil environment. I keep the area between the citrus trunk and the tree drip line free of other plants so the feeder roots can get air and nutrients. I apply potash, manure, compost, organic citrus blend fertilizer, calcium, azomite, and/or cotton seed meal to the trees around the drip line about every quarter during the fertilization days of the moon cycle. I tend to leave the chickweed that pops up in those areas; it’s roots are thin and shallow and it will die quickly when the heat returns and plants need more nitrogen for increased growth.
For more information about weeds, their uses and indications, here are some more references:
Tenth Acre Farm – http://www.tenthacrefarm.com/2014/08/5-weeds-you-want-in-your-garden/
Rodale Institute – http://www.rodalesorganiclife.com/garden/listen-your-weeds
Nature’s Way Resources – http://www.natureswayresources.com/infosheets/shootmessenger.html