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Integrated Pest Management Jan - Mar 2018 Missouri Environment & Garden Amaryllis after the Holidays by David Trinklein Among indoor flowering plants, few can match amaryllis in The bulb received as a gift already will have a scape formed inside. grandeur. Its blooms are spectacular in size and come in many colors Exposure to moisture and proper temperatures will cause this scape including bright, cheerful red. In addition to being very colorful, it to elongate, mature and flower. Since amaryllis is tropical by nature, has the added attraction of being relatively easy to re-bloom and can plants respond well to high temperatures (both day and night). A continue to give pleasure to its recipient for many years. For those minimum of 70 degrees F. during the day and 60 degrees at night is who might have received an amaryllis for Christmas, now is the time ideal during the growth cycle of the plants. Temperatures lower than to start the care it needs to provide beauty next year. 50 degrees can be injurious and should be avoided. Amaryllis requires, on the average, from six to eight weeks from the beginning of growth The plant commonly sold as amaryllis actually is misnamed and is a to the production of flowers. member of the genus Hippeastrum, not Amaryllis. Hippeastrum is native to the tropical Americas whereas the true Amaryllis is native Re-blooming amaryllis is relatively easy, but the plant must be allowed to to Africa. Both are members of the Amaryllidaceae plant family. manufacture and store food in its bulb in preparation for the process. This “Hippeastrum” comes from the Greek word meaning “horseman’s is accomplished by exposing the plant to light as bright as possible during star”; a name most likely selected for this plant because of the the growth period that occurs after flowering has ended. Adequate water resemblance of its flowers to a star-shaped medieval weapon used by and fertilizer are essential for maximum food production during this period. horseman. For simplicity’s sake we will continue to refer to the plant After the danger of frost has past, moving the plant outdoors into a lightly as amaryllis in this article. shaded setting will facilitate growth and improve subsequent blooming. Most of the amaryllis sold today are In September, the plant should be hybrids developed by the Dutch brought indoors and water withheld. and were selected for their huge, This will induce dormancy, which showy flowers and forcing ease. It is should be maintained for several not unusual for a vigorous bulb to months. During its dormant phase, an produce up to six flowers, four to six amaryllis should be kept on the cool inches in diameter, per scape (flower side and should not receive water. The stalk). Since amaryllis is native to the leaves will wither and dry during this subtropical and tropical Americas, phase and may be removed. their tender nature forces us to treat The growth cycle (along with them as greenhouse or house plants blooming) can be repeated by forcing here in the Midwest. the plant out of dormancy by watering If you received a flowering amaryllis and subjecting it to warm temperatures plant during the holidays, keep its as described above. Repotting may be growing medium uniformly moist. necessary if the bulb has outgrown its Small bulbs may produce only one original container. scape, while large bulbs may produce Failure to flower one season does not necessarily mean the plant will not two or three. After the last flower fades, cut off the scape(s) and produce flowers the next season. However, failure to flower does mean place the plant in a bright location, if you are interested in having it that growing conditions were not adequate and corrective steps must be bloom again next year. Fertilize the plant with a houseplant fertilize taken. Elongated, pale-looking leaves on a flowerless plant is indicative according to label directions and allow the leaves to continue to grow. of inadequate light intensity, temperatures that are above optimum or, If a bulb was received instead of a flowering plant, amaryllis perhaps, a combination of both. production for the hobbyist is relatively straight-forward. Plant Amaryllis is a bit easier to re-bloom later in the winter. If there is no the bulb in a well-drained, highly organic potting mix that retains need or desire to have the plant in flower for the holidays, allow it to adequate moisture. A mixture of sphagnum peat, vermiculite and grow outdoors as late as possible in the fall. Do not, however, allow it to perlite works well. Maintaining this medium in a slightly acid state be exposed to cold temperatures. Bring the plant indoors before frost, is desirable. Containers often are furnished with the amaryllis bulb withhold water and allow the leaves to fall off. Place the dormant plant in in a kit. If such was not the case, choose a container at least two a bright location and start watering again in January or February for late- inches wider than the diameter of the bulb. winter or early spring flowers. Organic Management Options for the Japanese Beetle at Home Gardens by Jaime Pinero and James Quinn One naturally occurring bacterium Introduction that is commercially available is Japanese Beetles were accidentally Feeding frenzy called Milky Spore®, which is an introduced to the east coast in 1916 Feeding on plant option for controlling grubs in the in a shipment of iris bulbs. Since then tissue by adult soil that damage the lawn. When they have slowly and steadily made Japanese beetles spores of Milky Spore are ingested by Japanese beetle grubs, they die their way westward. The Japanese causes the release of beetle has become a major pest of and in the process they release crops, lawns, and ornamental plants plant volatiles from billions of new spores into the in Missouri. In fact, 2017 was the the damaged sites, surrounding soil. One example of year when the highest populations and of additional a commercially-available formula- were recorded thus far. To control pheromones from tion of Milky Spore is produced by this invasive pest, many people are females. This results St. Gabriel Organics. Cost to treat 2,400 square feet is about $30. This interested in using less or no insecti- in aggregations of cides, and other control options that product is most effective when ap- beetles, triggering are safer for home-owners and also plied in early- or mid-August, when compatible with organic production. a feeding frenzy. If the grubs are actively feeding. The you are able prevent soil must be above 65 degrees F. It Seasonal Activity of beetle aggregations works best to apply it just before Japanese Beetles by dislodging or killing rainfall, or consider watering in lightly after application to soak into In mid-Missouri, significant numbers the first arrivers, soil. The number of applications of Japanese beetles begin emerging you may be able to recommended by the label should be in mid to late June, the population limit the damage. considered, applying Spring, Sum- peaks the second week of July, and Conversely, if a mer, and Fall for two consecutive declines by early August. The timing years (six total). While this signifi- of the onset and end of Japanese bee- feeding frenzy starts, cantly increases the expense, it is tle adult activity may vary by a couple it will be difficult to claimed to give faster control, for up weeks depending on weather. For remove the beetles to 20 years. instance, if warm, humid conditions unless insecticides occur – they will emerge earlier. If it’s are applied. cold and rainy, they may not become active until late June. Daily feeding behavior is also subject Organic Management to weather. If you are checking your plants, you might not see any beetles Options for the Japa- on a cold, rainy day – but don’t as- nese Beetle sume your pest problems are over! Biological Control Thousands of Japanese beetles may Japanese beetles are not native to the burst from the ground on the very Japanese beetle larvae killed by next day if it’s warm and sunny. Feed- U.S.A., so there are very few natural Heterorhabditis bacteriophora next to two ing damage to plants can happen enemies that could keep them in check. healthy larvae. Picture by Whitney Cranshaw, within 48 hours. Your pest manage- Some species of parasitic wasps that Colorado State University, Bugwood.org ment strategy should be “proactive” attack Japanese beetles in the grub and not “reactive.” Don’t wait to see cata- adult stages have been introduced into There are also several species of strophic damage before acting. the country, but they are not com- nematodes (tiny round worms) that mercially available. However, there are attack Japanese beetle and other soil- some pathogens (organisms that cause dwelling grubs. NemaSeek® consists diseases) that attack the grubs in the soil. MEG Jan-Mar 2018 2 Volume 24, Number 1 of live beneficial nematodes that ac- system is deployed outside the tively search for grubs in the soil. Cost Before applying a pesticide, always cropped area. For blueberries, 7 to treat 1,600 square feet is about $30. thoroughly read the label and make sure traps per acre have proven to be Nematodes need to be mixed with wa- to use the proper personal protective effective at suppressing beetles ter to apply using a backpack sprayer. equipment. from the cropped area. By using Usually, two applications—7 days mass trapping, over 15.5 million apart, are recommended. Soil temper- Mass Trapping Japanese beetles have been killed in ature needs to be at least 44 degrees F a 6-year period in two farms without and it needs to stay moist (water every Mass trapping is a topic surrounded spraying the crop with insecticide.