Weeding Ideas, Early Blooms

Gardening friends are pulling weeds that sprouted during our recent warm days and wishing for effective treatments. There are no quick and easy solutions to weed problems, but the longer view dictates “weeding before seeding.”

Ever optimistic, I am testing an organic pre-emergent herbicide that is based on corn gluten, a natural material that discourages the formation of roots. It’s neither cheap or 100% effective, but might be worth a try. For more information on a pelletized product, visit eartheasy.com and search for “corn gluten.” For a liquid version, go to amazon.com and search for “Green It.”

Another organic approach is the application of vinegar, which can kill really young weeds. Household vinegar (5% acidity) has some effect but horticultural vinegar (20-30% acidity) works better but dangerous to the user.

Other organic weed killers are based on clove oil will kill at least the top growth of mature weeds.

Still, the best, cheapest and most reliable way to kill weeds is pulling or digging them out by their roots.

Take a break from weeding to anticipate the coming spring and enjoy plants that are in bloom now in your garden. As I look around, I am pleased to see these early bloomers:

Wagner’s Sage (Salvia wagneriana), a large sub-shrub from Mexico and Central America has gorgeous hot pink or pink and white bracts that are greatly appreciated by hummingbirds as well as gardeners.

Wagner’s Sage

Salvia blossom - scarlet

Big Mexican Scarlet Sage

Big Mexican Scarlet Sage (Salvia gesneriiflora ‘Tequila’), another treasure from Mexico and Central America, produces brilliant red flowers with a striking black calyx and grows about ten feet high in California gardens. My neighbor has a stand of this plant that has grown fifty feet wide and well over fifteen feet high with support from adjacent shrubs.

 

 

 

 

Wonga Wonga Vine (Pandorea pandorana), from Australia, is a vigorous, woody vine that climbs with support from a tree or large shrub, or a trellis of some kind. Its popular varieties have differently colored blossoms: ‘Snowbells’ (white), ‘Ruby Belle’ (pinkish), ‘Ruby Heart’ (cream with ruby blotch), and ‘Golden Showers’ (yellow). My specimen grows on 2” x 2” rail attached to a fence and produces white racemes. The plant usually flowers in spring; we’re still in winter, so this is an early bloom.

Other plants now in bloom include

  • Beach Sage (Salvia africana-lutea), interesting wrinkly, golden brown flowers, from South Africa.
  • Winter Daphne (Daphne odora ‘Aureomarginata’), delicate blossoms, fine fragrance;
  • Common Hyacinth (H. orientalis), one of the earliest bloomers
  • Trumpet Daffodil (Narcissus ‘King Alfred’ probably), a cheerful yellow blossom
  • Blue Hibiscus (Alyogyne huegelii ‘Santa Cruz’), a large, frequent blooming evergreen shrub

A plant to watch is the Chinese Ground Orchid (Bletilla striata), which is now preparing for early blossoming. This hardy orchid, native to China, Japan, Taiwan, and Vietnam, is delightfully easy to grow. It is a terrestrial orchid that requires no extraordinary care and produces rose-mauve blossoms that resemble a miniature Cattleya orchid flower. An established clump will produce dozens of flower spikes. I recently moved several plants from too-shady spots into large shallow containers, anticipating the development of clumps in a couple years. They are not particularly frost-tender, but recent frost warnings encourage moving the pots under shelter.

As always, gardening involves the exercise of patience.

Wild Geraniums in the Landscape

Recently, I’ve dug a lot of geraniums of my garden because they had grown exuberantly in the wrong place. I will describe these interlopers later in this column.

Plants that grow where they are not wanted have been called “weeds,” but that’s not an appropriate name for these plants because they are garden-worthy in all respects. A better description would be “prolific,” which is a desirable trait for garden plants.

My project to manage geraniums in my garden prompts a brief overview of the Geranium family (Geraniaceae),

Let’s first review the confusion over genus names in this family. Today, we understand that the Geraniaceae includes three principal genera: geranium, pelargonium, and erodium. During the 1750s and 1750s, when Carl Linnaeus was naming plants, he included all three of these genera as geranium. In 1789, another botanist concluded that geranium and pelargonium were, in fact, different genera. Others later decided that erodium was also a separate genus. Despite this long-standing agreement on these names, many gardeners still call pelargoniums “geraniums,” although they are quite different, each with desirable characteristics.

The name “geranium” refers to the crane, while the name “pelargonium’ refers to the stork, but I actually do not find that helpful.

The true geraniums are often called “wild,” although many popular varieties are hybrids, or “hardy,” even though some geranium species don’t do well in winter. (Pelargoniums are not winter-hardy.)

The genus Geranium includes 422 species of annual, biennial and perennial plants. Most geraniums are native to the eastern part of the Mediterranean region, but they are found throughout the temperate regions of the world and the mountains of the tropics.

An excellent guide to this family of plants is the website Geraniaceae, which is maintained by Robin Parer, a very knowledgeable person in Marin County.

The site describes plants within the three principal genera of the Geraniaceae. It lists many species of Geraniums in the following groups (with numbers of species): Annuals (6); Borders & Bedding (169); Ground Covers (86); Rock Gardens & Containers (39); Scramblers & Crawlers (23); and Shade (83).

Ground cover geranium

Geranium cantabrigiense

The geranium I dug out of my garden is G. x cantabrigiense. The species name is based on the Latin name for Cambridge, England, where the hybrid was developed. My plant is the cultivar ‘Biokovo’, which is a natural hybrid discovered in Croatia’s Biokovo Mountains. The Perennial Plant Association named this plant 2015 Perennial Plant of the Year. It is an excellent ground cover that grows up to a foot high and displays white blossoms with a pink throat and prominent pink stamens. The blossoms generally open in late spring and continue into the fall, but have appeared early this year.

This plant had spread in several parts of my garden. I had yards and yards of it! I removed a 3’ x 30’ bed that amounted to perhaps 25 percent of the total so plenty continues to grace the landscape and will need future control. I removed these plants because they were growing in an area I had designated for natives of California and Mexico; I have planted this area with seeds of two varieties of the Four O-Clock (Mirabilis jalapa), which is a Mexican native and another vigorous grower.

Geranium leaves

Geranium canescens

Another geranium in my garden is G. canescens, which is a larger, relatively rare South African species that has been growing in my garden for only seven months. The species name means “to become grey, to become old,” but the plant, which is luscious green and doesn’t appear to deserve that name. It has large, deeply lobed leaves, and will display pink flowers later in the spring.

To explore the garden possibilities for the geranium, visit Geranaiceae.com or talk to Robin Parer in person at the San Francisco Flower & Garden Show, which returns to the San Francisco’s Cow Palace, April 4–8, (www.sfgardenshow.com/).

Hardy geraniums can be fine additions to the garden landscape.

Selecting Cannabis Seeds

After happening upon a month-by-month checklist for growing cannabis, beginning about now, my curiosity took over and I searched for seeds for my first legal marijuana grow.

This column is intended for gardeners who have interest in personal (non-commercial) cultivation of marijuana, and lack experience in this area.

Seeds are easy to find on the Internet: just search for “marijuana seeds.” They are more expensive than the seeds of familiar garden plants because they are still new on the gardening scene. Weed seeds are all too easy to come by, but several cannabis cultivars have been brought to the market, each with a combination of desired characteristics, so the marketplace is thriving.

While exploring the options, the basics of seed selection and marijuana cultivation gradually came into focus.

An important option relates to the fact that cannabis is normally dioecious, meaning that it produces separate male and female plants. Occasionally, however, some plants can be monoecious, having male and female flowers on the same plant. Unfertilized female flowers produce the best buds, so some growers will either grow only female plants or identify and remove male flowers before they can produce pollen. With a little care, one could pollinate female flowers selectively to produce seeds for a subsequent generation of plants.

Cannabis breeders have developed “feminized” plants, i.e., without male chromosomes, which are available as an easy option for growing buds of desirable quality. These plants can only produce unfertilized female flowers. A gardener could either propagate cuttings from a feminized plant to produce another generation of plants or buy seeds of the same or different cultivar, choosing from wide and growing range of possibilities.

Another important option in seed selection involves the recently modified growth cycle. Natural (“wild”) marijuana plants are photosensitive and dependent on the onset of longer nights to trigger the development of the desired buds. Growers have had to simulate this transition from the vegetative stage to the flowering stage by providing high light levels during the vegetative stage followed by periods of darkness to prompt the flowering stage. Cannabis breeders have made this process easier by developing “auto-flowering” plants that progress to the flowering stage after the passage of a certain amount of time, rather than in response to light changes. Auto-flowering plants still grow during their vegetative stage best under high light levels, but such plants can be grown at any time of the year and without burdensome manipulations of light and darkness.

A third option concerns the mature size of the plant. Using wild plants again as our reference, the most popular species, Cannabis sativa, when grown outdoors without controls can reach or even exceed twelve feet in height. California law limits personal cultivation of marijuana to indoor sites, e.g., a greenhouse, where plants are less likely to grow to an unmanageable size and be trained to be smaller, bushier and more productive of buds. Still, breeders have developed so-called compact plants that will remain under four feet tall at maturity.

There are additional variables to consider in seed selection: the plant’s relative strength of psychoactive THC versus medicinal CBD; a given strain’s balance of C. indica and C. sativa; and the character of the plants’ effect on a user, which the individual user surely would moderate.

The curious gardener might wish to explore this horticultural byway. Those that do should comply with state law and local regulations regarding personal cultivation of marijuana.The Cannifornian website is a great source of information on regulations in California’s cities and counties.

Regard gardening as adventure!

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