Most of the vegetables we eat on a regular basis are cultivated adaptations from some older source. A good example is broccoli, which is the very same species of plant as cabbage, cauliflower, Brussels sprouts, kale, and kohlrabi. All of these were bred over time from a common ancestor. The modern tomato, even in its v Covers subjects about horticulture and pest management for the grower and associated industries Florida Nursery Grower Landscape Association Certified Horticulture Professional classes
Growing Edible Weeds
Most of the vegetables we eat on a regular basis are cultivated adaptations from some older source. A good example is broccoli, which is the very same species of plant as cabbage, cauliflower, Brussels sprouts, kale, and kohlrabi. All of these were bred over time from a common ancestor. The modern tomato, even in its various heirloom forms, is highly developed through generations of breeding from its original wild form. Plant breeding is in no way a bad thing — rather, it has given us a wealth of variety from a handful of sources. There are a minimum of 296 varieties of peas being grown for food in the world, and more than 4,000 types of potato.
One of the basic principles of cultivating good food crops is the removal of all plants that would compete for space, nutrients, light, and moisture: Weeds. These plants grow quickly and seem to spread like viruses. They can easily take over a neglected patch of soil in no time. But how many of these end up in the compost heap rather than the salad bowl? How many of these garden foes are actually edible, nutritious, versatile, and delicious? It turns out that lots of them are. Growing edible weeds can be easy and rewarding.
But why would a gardener knowingly plant a row of weed seeds? The main reason is that, like any other crop, a row of dandelions or chickweed can be nurtured and cultivated to produce better flavour, succulence, vigour, and nutrient density. Thinking of these plants as crops turns the tables. They can be pampered, watered, fertilized — even weeded. They can also be easily controlled when they are grown in this intentional, managed way.
Consider the following weedy plants as food crops, and try a couple in your next vegetable garden. Amazingly, all of these are available as certified organic seeds.
Chickweed – It even has the word ‘weed’ in its name! Packed with vitamins, minerals, and protein, this is one of the tastiest and most succulent of all the wild greens. Take three cuttings or more from each sowing or use it as a cover crop — it breaks down as quickly as buckwheat to enrich the soil. Add a handful to salads or try some in a sandwich. Chickweed has a very mild flavour, so it should only be cooked briefly, but it’s probably better raw. It grows very well in containers, too.
Claytonia (Miner’s Lettuce) – Known also as Winter Purslane due to the succulence of its leaves and stems, this native west coast weed is actually sweet tasting, not tart like true purslane. It has such wonderful flavour that it really adds to salad mixes. Claytonia is quite cold hardy, which makes it one of the top candidates for winter harvest greens.
Dandelion – This plant hardly needs a description. Cultivated in good garden soil with a bit of balanced organic fertilizer, dandelions are delectable and nutritious. Eat the young leaves raw, or cook the mature leaves like spinach. Scatter the edible flower petals over salad, or collect the unopened buds (a lot of them are needed) for making dandelion wine. The bitter leaves are a rich source of iron and vitamins A, B1, B2, and C.
Goosefoot – A tall cousin of lamb’s quarters, this fast growing plant has large edible leaves that taste great and are high in fibre. Use the young, mineral-rich, magenta-tipped leaves raw in salad mixes. Save some of the high protein seeds for making bread or feeding wild birds. Harvest thoroughly, as Giant Goosefoot can reach 2m (6’) tall or more.
Huauzontle – A close cousin of Goosefoot! The close relationship between this ancient meso-American crop and quinoa are obvious as soon as it blooms. The seed head that follows produces bowls full of edible grains, but without the bitter saponin coating found on quinoa seeds. The immature leaves of huauzaontle are also edible.
Orach – This little known relative of quinoa produces bright fuchsia, succulent, tasty leaves unlike any other salad leaf. Its subtle, salty flavour earns it the colloquial name Saltbush . The eye-catching leaves simply pop in salad mixes. This variety is descended from wild mountain spinach originally growing in Montana.
Purslane – This hot weather plant produces thick, succulent, green leaves that add a light lemony crunch to salads. Cultivated purslane eaves are much larger than the wild type and the plant grows upright, not prostrate. It contains more Omega-3 fatty acids than any other vegetable. It can be cut almost to the ground, but keep two leaves at the base for re-growth.
Weeds And Seeds
The last post demonstrated the remarkable ability and unique features of aphids that allow them to rapidly boost their numbers and colonize their hosts in favorable conditions. What about weeds? What features give them the ability to rapidly colonize a potted crop or planted field? Many plants become weeds because they have the powerful trick of producing many many seeds. Seeds are dispersed by wind, insects, animals, or by their association with our nursery tools and machinery. Often, these seeds are long-lived in the soil. Consider these statistics:
Probably some unfortunate graduate students or field assistants in 1954 were given the task to count weed seed of hundreds of common weed species from about 50 plant families in North Dakota. The table above is just a sampling (Stevens 1957). In most cases a single plant, judged to be of average size and growing where competition was low, was harvested at maturity or when a maximum number of seeds could be obtained. The plants were air dried for two weeks or more, threshed and cleaned to re-move immature seeds, empty florets, etc. All of the sampling methods are described in the Stevens reference given below.
So basically left on their own, weeds have a profound ability to produce seed. Some seed are not viable, some germinate immediately, and some persist, perhaps for years, in the soil as a “seed bank”. This bank represents the holdings of weed seeds in the soil. Place a “deposit” of seed in this bank, and your “interest” is compounded in a big way. An interesting experiment with velvetleaf (Abutilon theophrasti) an important weed in soybean crops demonstrated this (Hartzler, 1996).
Velvetleaf is a prolific seed producer and seeds are long-lived. In 1990, replicated experimental plots were planted with soybean and then with one of three velvetleaf densities: 0, 0.2, and 0.4 plants per square meter. In subsequent years, the experiments were maintained in a corn-soybean rotation. Weed densities were determined at crop harvest for four years. As seen above– even with competition from the crop plants– velvetleaf density increased dramatically for years following the very sparse initial planting of the weed. There were even some velvetleaf plants seen in the untreated “0” plots, even though the plots were hand weeded to reduce seed production for 5 years prior to initiating the study.
The number of weed seeds in in the soil can range from near 0 to over 1,000,000 per square yard, and most weed seeds are between 0 and 5 years old. A small number of seed can remain viable for decades or more. With this knowledge, one of the most important principles of weed management is to “never let weeds go to seed”. Never.
Stevens O.A., 1957. Weeds, Vol. 5, No. 1 (Jan.), pp. 46-55
Hartzler R.G. 1996. Velvetleaf (Abutilon theophrasti) Population Dynamics following a Single Year’s Seed Rain
Weeds And Seeds
H orticulture in Southwest Florida is unlike anywhere in the world. Growing conditions are often ideal. Warm year-round temperatures, generous rainfall, and sunny days encourage plants and people. This microclimate offers a unique palette of foliage, flowers, and fruit.
Enthusiasm about plants is the beginning of being a great horticulturist. Knowledge, effort and experience complete the package. You are most productive and successful when you are familiar with seasons, soils, plant selection, attractive, useful arrangement, insects, diseases, weeds, and many unseen enemies of plant life.
Our objective is to give you a wide exposure to Florida ornamental horticulture, focusing on the southern zone, concentrating on Lee and Collier counties. Our classes are designed to give you useful, local information and to help you to pass the Florida Nursery, Growers and Landscape Association’s (FNGLA) Certified Horticulture Professional tests.
The Fall 2022 classes are now full and underway.
The next series will be in Fort Myers in January, 2023.
In our certification program we are responsible for identifying 259 palms, trees, shrubs, foliage plants, vines, ground covers and bedding plants. This link shows you clear photos , arranged by those categories.
In this blog I have some horticultural fun. At the bottom of the front page you can choose from categories like; Bedding plant trials, trade shows, salsa recipe, tomatoes, peppers, bad landscaping, garden benches, fairy gardens, poinsettias, and much more.