Visitors to my summer garden often stop in awe near my Nicotiana tobaccum. The question posed is almost always the same, “What is this, a four o’clock on steroids?” “No,” I laugh, “It’s a tobacco plant.” Nicotiana, which is otherwise known as tobacco, is available in a number of different species and cultivated varieties. Their delicate trumpets adorn plants that range from dwarfs that barely reach 8 inches all the way up to the old fashioned giants, like mine, that reach 4 to 5 feet high.
Nicotianas are a flower gardener’s dream. You can choose varieties with blooms in a range of colors including white, cream, rose, mauve, purple, and green. Some varieties have bicolored flowers, some have nodding flowers, and others hold their flowers up right. There are types that bloom all day, and others that are fragrant at night. They make great fillers in the perennial border, and they are versatile plants in the landscape. They do like sun, but they will tolerate quite a bit of shade. Humming birds are attracted to the flowers, which is a huge bonus as far as I am concerned. Nicotianas are long lasting in cut flower arrangements, and because of their toxicity, they are somewhat critter proof.
While the flowers are fabulous, organic gardeners often grow Nicotiana for its leaves. The leaves contain nicotine, much like commercial tobacco. Tea made from the freshly dried leaves of ornamental tobacco makes a great insecticide. Simply crunch up a few dried leaves, place them in a quart mason jar, and leave that in the sun for the day. Make sure you clearly mark your jar with a “skull and cross bones” and label it “Tobacco tea, poison,” just to make sure that no one mistakes if for homemade herb tea. This tea can be used as a drench for seedlings being harassed while still in there six packs, and it can be strained into a spray bottle to spray on older plants. The addition of a few drops of dish soap or insecticidal soap will help the tea stick to the plants.
Tobacco tea is effective for aphids, leaf miners, cabbage-worms, and many other pests. It is somewhat helpful for slugs, but not really helpful enough. (A sharp knife and a killer instinct are about the best cure for slugs. However, I am working on a few other less labor-intensive strategies. As soon as I have some success I will let you know.) Keep in mind that the tobacco tea is a poison. Poison kills living things. It may kill things you would rather keep living, so use it sparingly and as a last resort. I find, for aphids that a combination of ignoring them and attracting beneficial insects works just fine. (We will have more on both aphids and beneficial insects in up coming articles.) Cabbage-worms I can successfully hand pick. But when the leaf miners attack young plants, I definitely brew up tobacco tea.
When lessor measures fail, be sure to observe a few safety precautions. Don’t forget to clearly mark the container and definitely keep it out of reach of children. It is best to spray after dark, possibly with a flash light, to minimize poisoning the beneficial insects that are primarily active during the day. Also avoid soaking the ground in your garden beds, if at all possible. Nicotine is not good for your worms. (Worms are essential to the soil nutrient cycle.) Last but not least, it is recommended to wait at least 2 weeks before picking any produce that has been sprayed with tobacco tea.
If you are thinking of skipping growing your own tobacco and just buying commercial tobacco to use in your garden, think again. Commercial tobacco is not a good alternative to growing your own. The way commercial tobacco is propagated, irrigated, and cured makes it an outstanding source of plant virus and disease spoors. If you are going to use tobacco tea as a pesticide, it is much better to use your own home grown leaves selected from healthy vigorous plants. That way you know you will not be inadvertently trading a pest for a disease.
Fortunately, Nicotiana is widely available at most well stocked nurseries. Plants available range from inexpensive 6 packs often in mixed colors, to more costly gallon sized specialty specimens. Read the label completely to be sure the Nicotiana you choose is right for the spot you have in mind. Nicotiana can also be grown from seed. If you want to try some of the taller of more unusual varieties this might be the only way to go. Check out your nursery seed racks and see what they might have to offer.
Nicotianas are not the easiest plants from seed. First of all the seeds tend to be tiny, even dust like which makes them a bit difficult to handle. Next, to germinate and mature, the seeds and then the young seedlings need to be kept warm for an extended period of time. This around the clock warmth is sometimes difficult to provide in Northern California’s cool night time areas. It is a good idea to invest in a soil thermometer so you can explore potential locations to start your seeds. (Check with your local nursery or see the source in the next to last paragraph below.) The soil or seed starting media will need to be between 70 and 85 degrees throughout germination. Once the seeds have germinated 65 – 80 degrees is a good range until they are 3 – 4 inches tall, when you can begin acclimating them to the real world.
Avid gardeners have all kinds of ways to supply “bottom heat” to seed starting trays. Some folks utilize the top of the fridge, a shelf over the stove’s pilot light or some other warm spot around the home. Old fashioned wet/dry heating pads, food warming trays and other miscellaneous gadgets and appliances can be pressed into use. Just make sure you can maintain the temperature within the suggested range, and that you are not using something in a way that may cause a fire or electrical hazard. You can even purchase special heating arrangements intended to warm your seed starting soil. Ask at your local nursery or see the source in the next to last paragraph below.
Nicotiana, once past infancy, normally thrives in Northern CA gardens. It is not particular about soil, and will even survive in heavy clay. In hot summer areas or those with sandy or gravely soils, Nicotianas will need regular summer irrigation. If given a sheltered spot in the garden, they will often over winter, but they can look quite bedraggled by spring. In warm interior valleys Nicotiana may self sow if the seed pods are left to ripen and split. The seed pods themselves are a great bonus. While they are rather short stemmed, they are decorative enough to be used in dried flower arrangements or potpourri. For those who save their own seed to share and trade, Nicotiana produces copious amounts when it is happily situated in a warm sunny spot.
If your local nursery does not have the perfect Nicotiana to tempt you, check out: http://www.thompson-morgan.com They have yummy specimens to grow from seed that you're unlikely to find anywhere else. You can also call them to request a catalog: (800) 274-7333. If you are an avid gardener, you will love their catalog. They have a great selection of ornamental and edible plants; as well as everything you need to start your seed, including soil thermometers and several choices for bottom heat.
Copyright 2006, Harvest McCampbell, Published by The Hoopa Valley People Newspaper, May 2, 2006. Posted here with permission.