Archive for April, 2006

Greenhouse plants in pots, flats, or benches are completely dependent on the grower for their needs. Watering is perhaps the most important and demanding job of all. Most plants are largely made up of water. A growing plant gives off tremendous quantities of moisture (in the form of vapor) through its leaves; this is called transpiration. If water is not available in the soil so the plant’s roots can replace this transpiration, the plant will wilt and quite possibly die.

WATERING

With potted plants there is a simple and generally reliable way to tell when water is needed. Rap the pot with the metal part of the hose. A dull thud means the soil is moist, a sharp click that it is dry. Or you can be guided by the feel of the top-soil. If it is still slightly moist to the touch, the plant does not need watering. Plants growing in the unheated or cool greenhouse do not need as much water as those in a warm greenhouse. You will find, too, that plants in small pots dry out faster than those in large pots. As has been said, “There is nothing ‘thirstier’ than a healthy plant growing in a 2-inch pot, especially in summer.” The last three words rate re-emphasis, for in sunny, summer weather plants use water rapidly and the soil in the pots may become so dry you have to water twice a day or more.

Cyclamens and gardenias require frequent watering. They grow fastest when their soil is always slightly moist. Cacti and geraniums, on the other hand, do not need much water, although geraniums need more than is commonly supposed. Plants affected by a disease usually need less water than healthy specimens.

Remember this: It’s always better to under-water than to over-water. You want your plants to mature as quickly as possible so you can turn them into cash but they must be at their best. Keeping them too wet does not promote stocky growth. Many growers still prefer the tried and true watering method; that is, fill the pot up to the top with water and let it seep through the soil. For this to be practical (and require just one filling) there must be at least % inch of space at the top, more in large pots. Do not let plants stand long in water. Watering thoroughly at intervals is better than a slight moistening each day, which only reaches the upper soil and roots.

Of course, vigorously growing plants need more water than dormant or slow-growing ones. Water oftenest during hot summer weather and in winter when the sun is bright. Give less water during cloudy spells or when humidity is high. For example: Through one summer which was unusually hot, but with very high humidity, I found that plants in flats in my greenhouse required watering only twice a week; potted plants needed it only every other day. However, in hot but dry weather the plants in flats needed water at least three or four times a week, the potted ones every day, and often twice a day. If possible, water plants in the morning, so the sun can evaporate the water during the day. Wet foliage at night is prone to mildew or fungus troubles.

Syringing plants with a strong stream of water will remove dust and wash off red spider mites, but do not expose plants to direct sunlight until they have dried off. Sun shining on wet foliage causes burned spots, particularly on hairy-leaved plants like African violets and gloxinias.

Basement profits

A husband and wife living in Wisconsin have converted their entire basement into a fluorescent lighted area for African violets. The floor has been tiled with asphalt. Counters and fluorescent lighted showcases have been added to increase customer appeal. In this basement “greenhouse,” they strive to

25. The vigorous condition of these African violets is proof of the ideal

light that well-arranged fluorescent, incandescent setups provide. Wasted

cellar space is thus made profitable. (Photograph by Manning Bros.)

grow only the varieties of violets in greatest demand, and their customers come from hundreds of miles to purchase cuttings and small plants. They do no mail-order selling, but make a good steady profit from their over-the-counter sales.

A grower in Winterset, Iowa, earned enough money from the sale of light-grown house plants to pay for her greenhouse. Her specialty is African violets. Another Iowa grower, who grows violets under basement fluorescents makes enough profit from them to pay for all of her own clothing and that of two high-school-age sons.

A Missouri “amateur-commercial” grower, the wife of a retired physician, adds a substantial amount to his retirement pay through sales of violets grown under light in a basement and two upstairs bedrooms.

A pair of fluorescents placed under the shelf in my greenhouse annex give me considerable extra room for starting gloxinera seedlings and cuttings. Since we have no basement in our home, we have installed lights in our utility room and in my study. Under these setups are started many of the gloxinias, African violets, episcias, and various hybrid seedlings destined for sale.

Turn Your Basement into a Plant Room

A basement setup can be constructed by fastening one or more pairs of fluorescent tubes to a sheet of plywood and suspending it from the ceiling by chains or ropes. Enamel the plywood white to give increased reflection, and if the basement walls are dark, give them a coat of whitewash or paint. A table or counter to hold the plants should be centered about 18 inches under the light tubes. This distance will prove satisfactory for growing a number of plants. Those needing most light can be boosted up with boxes or inverted flower pots while the leaves of taller plants such as potted lemons or other citrus, hibiscus, and holly, among others, should just clear the light tubes.

If you don’t want to give over this much home space to plants, you may be able to fasten lights inside an old cabinet or chest and grow or propagate plants in it. Then there are plant-growing cabinets, mostly of metal, with lights installed in them. These can be purchased directly from the manufacturer and are advertised in most of the leading garden magazines.

Plant physiologists have discovered that a mistlike fog of water keeps tender softwood cuttings (cuttings from new growth) in such excellent shape they “just have to root!” Under these conditions of either constant or intermittent mist the cuttings don’t wilt and there is a minimum of trouble from fungus and rot.

There is a mist unit on the market that has been adapted from a larger commercial mist-maker system. It’s called the Mistic Bubble and is an excellent greenhouse space stretcher. This is a system for rooting soft cuttings outdoors, in sand under plastic with the use of electronically controlled mist. Harvey M. Templeton, Jr., Winchester, Tennessee, is the inventor of the system and the control known as the Electronic Leaf. With this portable system the plants get water automatically, as they need it, until rooting takes place. Then the temporary greenhouse cover is gradually removed and the plants are thus hardened to growing outside in the full sunlight.

The hemispherical shape of the Mistic Bubble is designed to let in light evenly all around as long as the sun hits the cover. The plastic covering has a pigment cast into it to protect the cuttings from excessive summer heat. The low capacity mist nozzle, using 1 gallons of water per hour, keeps the leaves of the cuttings wet at all times, promoting very rapid rooting.

The Mistic Bubble is 4 feet in diameter and has 12 square feet of planting space it will hold 1000 cuttings at a time. After they root the cuttings can be sold or planted out to grow to maturity. In the South, the Bubble can be used throughout the year. We are installing one of these units to use for propagation of herbaceous plants and conifer cuttings, which we will plant out as a basis of a profit-making nursery. We’ll start by lining out several hundred daylilies and iris plus a few rows of evergreens. Later we may include chrysanthemums (these too can be rooted in the Mistic Bubble), and a few Azalea mollis, the hardy species, which several dealers now carry and which can stand our hard Minnesota winters.

I have described this system not only because I’ve had experience with it but also because its basic principles apply generally to mist propagation in the greenhouse as well as in a purchased or homemade propagating case. Fog nozzles for water lines are available for those who wish to make their own setups. Complete mist propagation kits are on the market too.

The most popular plants for propagating under lights are the gesneriads. Leaf cuttings or plant divisions can be rooted by inserting them in your favorite rooting media vermiculite, peatmoss, sand, sphagnum moss, or a mixture of these. You can speed rooting by putting a transparent plastic “tent” over the pots or flats and placing them about 6 to 8 inches from the lights. Transplant the small plants as they appear, which sometimes is but a matter of 3 or 4 weeks.

Tubers and rhizomes can be rooted by placing them on peatmoss, sphagnum moss, or vermiculite. Keep the medium moist and place the planting about 4 to 6 inches from the lights. As soon as sprouts show, transplant the tubers to individual pots.

24. In the big greenhouse of Edna Roberts, York, Maine, supplementary

fluorescent lighting puts the lowest bench on a profit-making par with

the topmost. Waterproof installation is essential for under-bench units.

(Photograph by Genereux)

Start any of the gesneriads from seed by sprinkling the seed over sterilized, milled sphagnum moss, sand, or vermiculite. Cover the planting with a pane of glass or slip it into a transparent plastic bag. Seeds will sprout in a dark, warm area (70 to 75 degrees). As soon as you see the green flecks of new plants, place the planting as close as 3 inches from the light tubes. Here the seedlings will grow with amazing rapidity. By careful timing as to fertilizing and transplanting, you can have flowering gloxinias in 3 to 5 months and African violets in 4 to 6 months. (For additional information, see my book on Growing Plants Under Artificial Light.)

Whether you are using the greenhouse or are growing plants in a special room or area in the home, regular attention is essential to success with artificially lighted plants just as with sun-lighted plants. Try to keep daytime temperatures between 70 and 75 degrees with the usual 10 degree drop during the night. Increase humidity by setting the pots on moistened pea rock. Grow the plants in sterilized soil. Water them regularly, according to the needs of each plant. Spray plants with insecticide every second week, as a preventive. As plants grow, shift them to the next larger sized pot. Leave the lights on flowering plants 12 to 16 hours each day; 4 to 8 hours per day for foliage plants.

If the plants produce long willowy foliage, they are too far from the lights. Set them on boxes or inverted flower pots to boost them closer. If leaves turn yellow and hug the pot, plants are probably getting too much light. Move them farther from the lights.

With stationary fixtures, aim for 18 inches between light tube and plant table to allow head room for plants in 4-inch pots. If you grow larger plants, fasten the lights a greater distance from the table or, better still, operate them on a pulley so you can regulate distances to suit plants.

As you experiment, you will find the proper distances. Here ‘ is a rather general rule to guide you. Light-loving plants, such as gloxinias and many other tuberous gesneriads, cacti, coleus, and wax begonias grow best with about 8 inches between light fixture and pot rim. African violets, rex begonias, and episcias, among others, thrive when space is about 11 inches. Foliage plants, philodendron, ivy, and cissus can be set 18 to 24 inches from

the source of light.

If you wish that you lived in a paradise like Florida or Hawaii, then maybe you can design your landscape to look like your own tropical getaway. All you need to do this is a little creativity and some time. A beautiful tropical landscape will impress all your friends and neighbors and leave them green with envy.

Plants make all the difference

When you are planning a tropical backyard, you will want to include a lot of plants. Lots of greenery and wild colors will enhance your tropical illusion. There are plenty of plants and flowers that will grow in any weather conditions. If you are not sure what to use and what plants and flowers are best, then ask someone at your home and garden center.