Month: July 1999

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Growlabs

What better way to help children learn about gardening than to encourage them to grow plants themselves? That is the idea behind the GrowLab program for school children sponsored by the National Garden Bureau (NGB) in a joint venture with the National Gardening Association and the National Science Foundation. In a matching funds program, NGB and participating seed companies donate 6 GrowLabs per year to schools (K-8) across the country. Each GrowLab is accompanied by a complete starter kit containing pots, potting mix, labels, fertilizer, insecticidal soap, watering can, and seeds.

NGB also provides recipients of GrowLab units with supporting curriculum materials such as videos and follow-up newsletters, and arranges for a local seed company or expert to “adopt” participating classes. These mentors are available as a resource for the teacher, offering advice and information in addition to replenishing seeds as needed.

Kinder “gardeners”

Brenda Kukay, a kindergarten teacher at the Mitchell School deep in the city of St. Louis, Missouri, has had her GrowLab for almost 6 of the 11 years she has been teaching. Hers was the first school district to participate in the NGB program, and she was among the teachers sent from 5 schools for training in Vermont. Partnered with the world famous Missouri Botanic Garden, over the years she has integrated the GrowLab into her science curriculum to the delight of classes.

Brenda introduces her kindergartners to science with GrowLab activities around seed planting, germination and plant growth. Her tiny ones learn by the inquiry method to ask good questions and then set about to answer them through a hands-on science experience. They sharpen observation skills as they watch for lettuce seeds to sprout. Then, when they harvest their lettuce crop, they enjoy eating the salad. They also plant peas, beans, corn, and other greens, depending on what seeds are available. In the spring they plant their young seedlings outdoors in a garden tended by the summer school students who plan to sell them to raise money for the program.

Brenda has a longtime interest in gardening and has cared for the ornamental garden areas at the school in her spare time. With this enthusiasm and the support of the periodic GrowLab newsletter, she guides her charges through the joys of growing. Of course, they are simultaneously learning other things. They learn math by measuring, estimating, and creating graphs and charts. Their writing skills are enhanced as they record their activities in their science journals. When publication resumes, they will write articles about their seed growing activities for the school newspaper.

Lots of Learning

In Brenda’s experience this is a program that teaches both students and teacher. She feels she is exposing some of her class to a totally unfamiliar world. She has discovered that some of these apartment-dwelling city kids are so removed from the natural growing cycle that they have trouble conceptualizing the future of the seeds they plant. She reports that, when asked what will be the result of planting tomato seeds, for instance, some students will venture guesses as wide-ranging as corn, beans, even a dog! She has had to do some research, herself, to master the technical intricacies of providing appropriate amounts of light for various crops.

The GrowLab program has had a halo effect at Mitchell School. Many of Brenda Kukay’s colleagues have shown an interest in what she does and are considering the potential of a GrowLab in their classrooms. The two official ones in her building are proving to be so popular that 3 more homemade versions have appeared in other classrooms. She, herself, is hoping to have a wheeled model that she can move about the room easily. One teacher, whose classroom lacks the space for a GrowLab has found room for a worm composting operation for her students. Their product is contributed to the growing activities in Brenda’s room. Teachers like the flexibility of the GrowLab units. They are useful at almost any grade or ability level. They can be integrated into various study units, or used as separate study units or for after school clubs.

The GrowLab program has influence beyond the school walls as well. Occasionally parents report that the children are asking questions at home and taking an interest in plants. Some kids are strengthening bonds with gardening grandparents. Ultimately, students who learn with GrowLabs learn a lot more than just about plants–or even science.

For More Information

The National Garden Bureau considers children’s gardening one of its most important missions. The non-profit organization intends to continue donating GrowLabs to schools throughout the 21st Century. The Bureau and member companies have placed 21 GrowLabs in schools, and will donate an additional 6 labs this fall.

For more information about donating a GrowLab and other educational programs, please contact: The National Gardening Association, 180 Flynn Avenue, Burlington, VT. 05401 phone: 1-800-LETSGRO. Or visit their excellent website at WWW.garden.org where each month the kids and classrooms section features new lessons and articles from the Growing Ideas educators’ journal. The site highlights curriculum resources that support garden based learning, connections with e-mail pals in growing classrooms, and links to other plant and garden based sites.

What is a GrowLab?

GrowLab units donated to classrooms across the nation are commercially designed and constructed for self-contained, tabletop seed-starting and seedling management. Essentially a metal frame that supports two 4 foot long easily adjusted fixtures that hold fluorescent growing lights, each unit is 52 inches wide and 23 inches deep, 39 inches tall. Each is equipped with a timer, convenient trays to hold seedling containers or potted plants and a tent-like cover to help regulate humidity.

GrowLab activities

Suggestions for integrating the GrowLab into a science curriculum are provided in the materials that accompany the unit and subsequent issues of the newsletters. However, the only limits on its use are the imaginations of the teachers and students.

Propagation: germinating seeds, growing seedlings, rooting cuttings, repotting

Experimentation: with fertilizer, light, humidity, growing media

Production: bedding plants for sale or gifts; vegetables for eating

GrowLabs Promote:

Art
Botany
Business skills
Chemistry
Environmental studies
Geography
Mathematics
New foods
Plant identification
Recycling
Responsibility and follow through
Self-esteem
Scientific observation
Teamwork
Time management
Writing

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Dandelions & Potassium

Spring is here and our lawns look like they have the horticultural counterpart of the measles, but the spots are yellow, not pink. This leads to the stratification of gardeners into three groups. There are those who reach for an herbicide to get rid of dandelions, then the more environmentally concerned who pinch off seed pods and dig up what they can – and lastly those who simply accept things as they are since after all, it’s only Taraxacum officinale, alias dandelion. The first group of gardeners may receive some relief as a result of what American ecologists saw at the Rothamsted Experimental Station in England. They noticed there was a mosaic of plots in this grassland. Some plots, yellow with dandelion blooms, were bordered by plots where dandelions were almost absent despite the heavy rain of dandelion seed received annually. They found that the dandelion population was related to whether potassium had been applied.

Following tip on this observation the Minnesota group studied the effects of potassium on dandelions and five lawn grasses in a greenhouse environment and the relationship between the amount of potassium in plant tissue and the density of dandelions of lawns in Minnesota. In the greenhouse study potassium was highest in dandelion tissue, suggesting dandelion has a hearty appetite for this element. They also found that in pots given a low potassium fertilizer the dry weight of dandelion, fescues and orchard grass all decreased BUT dandelion suffered the greatest loss, down to 81% of its weight in pots given a complete mineral supplement.

The lawns selected for study were restricted to those that had not been fertilized, treated with herbicide or hand-weeded for several years. The amount of cover as well as the density of dandelions correlated with the tissue potassium content. When the plant tissue level of potassium was low, the dandelion density and cover in the lawns was low. Based on these results it is suggested that one step gardeners could take right now is to use a fertilizer of ammonium sulfate or ammonium phosphate, However, this would not be good for lawns of Kentucky bluegrass which is almost as greedy for potassium as dandelions.

At this time it is unclear how widely applicable the strategy of controlling weeds through nutrient limitations will turn out to be. In the opinion of agricultural and weed scientists, it appears to be an area that is worthwhile to follow up, for the relationship between soil characteristics and weeds is only beginning to be understood.

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Integrated Pest Management

Hawthorn lace bugs plague many plants in the rose family including hawthorn, apple, cotoneaster, and firethorn. Adults have partially transparent wings with an intricate lacy pattern and opaque areas. Look for a whitish speckled appearance on the tops of leaves. The lower surfaces of the leaves are often discolored with excrement and cast skins of the developing nymphs. Use horticultural oil or a pesticide containing acephate and be sure to spray thoroughly on the underside of the leaves if large numbers of lace bugs are present.

During periods of dry weather, allow your lawn to go dormant to avoid turf diseases and to discourage weeds. If a green lawn is a must, water early in the morning and adjust your mowing height above two and a half inches.

Adult Japanese beetles feed on the foliage and flowers of over 300 different plants during the hot, summer weeks of July. These beetles have a metallic green body with reddish-bronze wing covers and are the size of a coffee bean. After mating, adult females lay eggs in turf. Dry soil conditions kill many of the eggs, so avoid watering lawns in July and August. To prevent serious damage, handpick the beetles daily in the early morning when they are less active and drop them into a bucket of soapy water.

Powdery mildew, a fungal disease that attacks the leaf surfaces of many flowers, shrubs, and trees, is a growing problem for dogwoods. Look for white powdery patches on the upper surface of new growth. This disease can cause the new growth to be curled and deformed, and often reduces the growth of very small trees. Loss of photosynthesis can also weaken the trees making them more susceptible to dogwood borers and canker diseases. To prevent powdery mildew, avoid heavy doses of nitrogen fertilizer, overhead watering, and excessive pruning. These practices can force tender new growth that is more susceptible to the fungus. Provide your trees with good air circulation, prune out dead wood, and place a thin layer of mulch over the root system. There are disease-resistant flowering dogwood cultivars available also such as ‘Cherokee Brave’ and ‘Sweetwater’.

Monitor your boxwoods for boxwood mites. These spider relatives are small, red, and slow moving. Yellowish stippling in a linear pattern appears on old foliage when mite populations are high. Beat test by tapping a stem onto a piece of white paper. Consider spraying with horticultural oil when the count exceeds twenty or more mites per beat. Do not spray if faster moving predatory spider mites, or small, jet-black mite destroyer ladybugs are present.

Monitor your plants for thrips. These very small insects may be found in the flowers and leaves of many plants. Thrips are orange to brown in color and they scrape leaves and petals with their mouthparts. Look for white streaks, curled leaves, and stunted growth. Find thrips by using the beat test. Gently tap a branch of the plant onto a piece of white paper and look for the thrips on the paper. If you count more than five thrips and the foliage shows signs of damage, you may want to consider spraying with a pesticide labeled for thrips. Before spraying, look for minute pirate bugs, small black insects that feed on thrips. They also feed on pollen, so look for them on the flowers. Refrain from spraying if these predators are present.