Evocative is the word that comes to mind when I see canna lilies. I have visions of jungles, plants with giant unfurling leaves, sunshine and bright red, yellow, pink or fiery orange flowers. Hailing from South Africa, New Zealand and tropical and subtropical regions of the Americas, cannas are just one of the exotic flowers from the bottom half of the globe that thrive here.
Cannas require only four hours of full sun to produce nonstop color throughout the summer and often long into fall. Plant them in full sun or partial shade. A bonus for Napa Valley gardeners living in the hills and dales of our county: most deer will leave most canna alone.
Canna comes from the Greek word, kanna, which means reed or grass. The plants are not actually related to lilies at all. Canna is also referred to as Indian shot because of their hard, black, round seed, which is used as a bullet in handmade weapons.
The hosho, a gourd-like Zimbabwean musical instrument, has canna seeds enclosed, another traditional use for this plant. I can attest to the seeds' pellet-like appearance. They are very round and very hard. I bought seeds and then read the seed packet to discover it would be at least three years until the plants bloomed. Life and my attention span are short. I ordered tubers. They will arrive in February and be verdant and blooming by May.
In many areas of the country, canna lilies need to be dug up in fall and stored through winter before replanting in the spring. We are lucky here. With our comparatively mild winters, and with careful consideration of the planting site, cannas can stay in the ground all year and are considered perennial in Napa Valley. Planting cannas on the south side of a wall, fence or building shields them from cold, harsh winds and provides plenty of sunlight for good tuber formation.
Cannas spread by fattened extensions of the stalk known as rhizomes, which are storehouses of carbohydrates and proteins. The leaves capture those four hours of needed sunlight and, through photosynthesis, convert the light into proteins and carbohydrates that feed and enlarge the rhizomes. The size and health of the rhizomes determine the size and health of the glorious blooms you will reap the following year.
Cannas begin blooming in early summer and are still blooming now in Napa County. One gorgeous display is the eye-catching bed of scarlet cannas in front of Sutter Home Winery as you enter St. Helena from the south. They are stately, magnificent and gloriously red.
Although it is not time to plant cannas now, it is the right time to order for the best selection. Nurseries are filling canna orders now for planting in February and March.
If you already have canna lilies in your garden, let the leaves die back naturally, then cut them at ground level. A little extra mulch will protect your canna rhizomes through the coldest months.
Plan where your canna bed will be in the spring. Cannas are not particularly fussy and can tolerate a wide variety of soil. For the happiest and ultimately showiest plants, provide loose, friable soil amended with manure, compost and high-nitrogen fertilizers.
When it is time to plant, space your rhizomes about 18 inches apart or follow the directions for spacing from the supplier. Plant them about 2 inches deep, placing the rhizomes horizontally with eyes facing up. If the eyes are not obvious to you, they will still find their way to the sun.
When the soils warm up and cannas begin to sprout, give their root areas a good soak once a week. If the weather is especially hot, water every other day.
Cannas have spectacular blooms, but some varieties have even more attention-getting foliage. Their broad leaves remind me of banana plants and come in colors ranging from bright lime- green to blood-red and purple. Leaves can be striped or variegated.
Dwarf cannas produce clumps reaching just a foot or two in height, while giant cannas range from six to eight feet. Other varieties can reach eight to ten feet in height, making a vibrant and dramatic screen. Single plants can be bold focus points.
Local nurseries will have canna rhizomes in the spring, but for the best selection and the opportunity to learn more about cannas, check online sites and order now. Bring a little bit of the tropics to your Mediterranean garden.
Workshops: U. C. Master Gardeners of Napa County will conduct 2 January workshops in 2019:
"Rose Pruning" on Saturday, January 5 from 10-12 noon at the UCCE Meeting room, 1710 Soscol Ave, Napa. Get all your Rose pruning questions answered at this interactive workshop. Topics include rose types, how and when to prune, what tools to use along with tool care, safety, and sanitation. For registration Online Registration (credit card only) or Mail-in/Walk-in registration (check only or drop off cash payment).
“How to Plan and Plant a Home Vineyard” on Saturday, January 12, from 9 a.m. to 1 p.m., in Yountville. Join our Integrated Grape Team members to learn techniques for planning and planting a home vineyard. The workshop will be held at a new home vineyard planted last year. Learn the necessary planning steps, become familiar with the checklist of activities, methods of determining the proper rootstock, selection of wine grape varietals for specific locations and estimated yield calculations. Review our calendar timeline for planning, site preparation, initial planting and timing of the first harvest for a new home vineyard. Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http:/napamg.ucanr.edu/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
Planting Cover Crops Enriches the Soil.
By T. Eric Nightingale
UC Master Gardeners of Napa County
The long summer of vegetable gardening can leave your soil in need of some rejuvenation, a perfect job for cover crops. Also known as “green manure,” cover crops are a natural and easy way to keep your garden soil healthy. They return nutrients to the soil, improve soil texture, prevent weeds and reduce erosion. The most effective and frequently used cover crop plants are legumes, grasses, grains and brassicas.
Returning nitrogen, a primary plant nutrient, to the soil is possibly the most important role of cover crops. Legumes are extremely good at this. They nurture Rhizobia, bacteria that converts nitrogen in the air into ammonia. Plants can later process this ammonium to obtain nitrogen from it. Rhizobia can't live in the soil on their own, however, so they use the roots of certain plants as a host. Some companies even sell seed with Rhizobia added to the mix. Legumes used as cover crops include fava beans, hairy vetch and clovers.
Brassicas such as radish and mustard are widely used as cover crops in vineyards. You have probably seen them flowering around Napa Valley. These plants grow deep (sometimes as deep as four feet), strong roots that break up the soil, letting water flow deeper into the ground.
Well-hydrated soil not only helps your plants, but allows for more soil organism activity. Grasses such as barley and ryegrass also help to break up the earth, but also allow for the introduction of high amounts of organic matter when they are turned back into the soil. It is common to use many different types of cover crops, in a mix, to provide as much benefit as possible to your garden.
Helping to retain moisture, improving soil texture and increasing fertility all contribute to a robust soil ecosystem. When this system of microbes, fungi, bacteria and other organisms is functioning as intended, the likelihood of soil-borne diseases greatly reduces. Even a garden needs to eat its greens to stay healthy.
Fall is a great time to plant cover crops, since many gardeners take a break between vegetable crops. You can sow cover crops directly from seed, broadcasting them by hand over the soil after tilling it lightly. Cover the seeds with a thin layer of soil to protect them while they germinate. You can add a small amount of fertilizer to give the young plants a jump-start on life. You will get a large return on this small investment when the plants grow.
Cover crops can also be used in the summer. Grasses such as sorghum, soybean and cowpea are often grown at this time. Also used are buckwheat and sunflower, giving the added boon of attractive flowers.
When the cover crops are at the end of their lives or you want to plant something else, turn them into the earth. Their organic matter will break down and further improve the soil. Alternatively, you can mow them and leave them on top of the soil as a mulch. They will eventually decay but in the meantime will further decrease water loss and erosion.
Cover crops also suppress weeds by blocking the sunlight, keeping weed seeds from germinating. If they are left on the soil surface as a mulch, they continue their weed-prevention duties. Some cover crop flowers feed bees, and fava beans, a popular cover crop, are edible and delicious.
There has been extensive research and testing on cover crops in recent decades. Their wonderful features make them sound like a cure-all for anything that ails your soil. In truth, they are one of many contributors to a healthy and productive garden. There is no doubt, however, that any garden will benefit from cover crops.
Workshop: U. C. Master Gardeners of Napa County will hold a workshop on the different kinds of poinsettias and other potted plants for holiday decorating using color and shapes. The workshop will be held on Thursday, December, from 7:00 p.m. to 8:00 p.m., at the Napa County Library, 580 Coombs Street, Napa. This is a free workshop and registration is not required.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County (http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
By Penny Pawl, U.C. Master Gardener of Napa County
Some time ago I wrote a column about African keyhole gardens. These innovative gardens are circular and have a place in the middle for worm composting bin. The design has performed so well that you can now buy a wooden kit for such a garden.
Last winter, I had an invasion of gophers who were eating my produce before I could. All my raised beds needed to be emptied and new wire put in the bottom.
I had been thinking about adopting the keyhole garden method of composting. Here was the opportunity to put my plan into effect.
My helper and I cut the bottoms off of two garbage cans so the worms could move back and forth. Then we drilled holes all along the sides. These garbage cans were placed in the bottom of the beds right on top of the gopher wire. Then we surrounded them with soil, keeping the rims of the cans above the soil, and put the lids on.
Next I had to supply the bedding for the precious red wiggler worms I planned to add to the cans. Red wigglers are used in composting because they are the only worms that eat decomposing materials such as kitchen scraps, coffee grounds and plant waste. Any seeds that end up in the compost—such as seeds from watermelons or tomatoes—may reseed in the bin or when you spread the compost around, so be careful what you put in the bins. I once had a compost bin full of maple seedlings because I had added maple leaves.
The idea behind this type of composting is that the worms will move in and out of the cans and, as they do, will take some of the compost with them. By this method, the compost gets spread around and helps the plants thrive. Worm compost is a balanced fertilizer and helps improve the texture of your soil.
I fill the bins with plain cardboard, which the worms love, as well as newspaper, kitchen scraps and soft trimmings from plants. On top of the bedding, I put large black plastic bags to keep the bedding moist. Something good is happening in there.
I have noticed that these cans seem to dry out faster than my regular compost bins. Maybe moisture leaches out of the bins into the soil. I check the bins often and water once a week with a garden hose. I also noticed that these bins were warmer in winter than my free-standing bins, which is good for the composting process. The soil around the bin must be keeping it warmer.
Online I found red wigglers from Africa. They are bigger and longer and eat more. I put them in one bin only so I could check on how they do.
I don't know if I will need to clean these bins out like I do with the free-standing ones. In spring, I plan to take out all of the uncomposted material and see what the bottom of the bin looks like. That's where the compost it.
Since I created these bins, they have attracted other creatures such as snails and slugs. And greeting me when I check the bins are some small toads that catch all the fruit flies. One bin has six tiny toads in it. I have also seen two alligator lizards and a black racer snake.
Workshop: U. C. Master Gardeners of Napa County will hold a workshop on “Garden Basics IV – Landscape Thoughts” November 3. There will be a discussion of firewise and hillside landscaping; rain gardens and swales; different mulches and permeable hardscapes as well as possible solutions to problem landscaping areas.Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
