Organic means of Disease & Insect Control

Dormant Spraying

Dormant spraying means exactly what it says; spraying done when the plant are in dormancy. That means no leaves or active growth should be happening.
Dormant spraying should be done immediately after pruning in spring and again in late fall when the leaves drop (usually late Oct.) Spraying dormant oil & lime sulfur when there is active growth will burn & damage leaves so if you snooze you loose in this instance! Your dormant spray will damage that tender new growth, setting your plant back, and possibly resulting in deformed growth.

A thorough dormant-spraying offers you your best chance for control of the various fungal diseases that plague roses: powdery mildew, rust, blackspot, insect pests, even downy mildew-all can be reduced by a careful dormant spraying.

Dormant Oil sprays and Lime-sulfur sprays are available at our nursery, and they are very reasonably priced. These materials are usually formulated for combined use. They may be safely used on roses now, while there is no foliage to be damaged. These oils coat the canes & suffocate the eggs & adult insects so spray each rose plant thoroughly, and spray the ground around it as well. Totally saturate the canes making sure you have not missed a minute crevice! Insects & tiny dust like spores of diseases hide in the tinniest of crevices & will come to life & multiply if you miss them. This application is essential if you are having spidermite problems. Those little unbearable pests are very hard to get rid of & a double dose of dormant oil really works wonders. In the fall & again in the spring giving them a double whammy.

Insecticidal Soap

When using insecticidal soaps, spray the entire plant thoroughly and repeat applications frequently. You may have to spray every few days at first until the infestation is under control. Apply in the morning, evening or on overcast days as not to burn tender new leaves if sprayed in full sun. Read carefully all label instructions. Soaps can burn some skin sensitive people or hurt eyes. If mixed too strong can cause severe damage to tender new growth! Rugosa Rose leaves do not like to be sprayed with anything especially insecticidal soaps! Spray only the parts where insects are a real problem. If possible use rain or soft water as soaps adheres better in water without high minerals content.

Organic Tips

To prevent spreading fungal diseases from plant to plant, disinfect pruning shears between cuts, dip the blades in a 10% solution of chlorine bleach( 1 part bleach to 9 parts water) or pure alcohol or peroxide Some rose growers submerge their bareroots in the bleach solution or peroxide before planting in spring or fall. Only dip them do not leave them in it for any length of time. This works really quite well! Canes need to be completely coated so dipping is the best!
Pheromone traps use specific (sex hormones) attractants to lure insects inside where they get stuck or trapped. They are also used to monitor and alert the grower when insects appear on the scene. Sticky cards are a great help for insects such as whitefly (yellow) and midges (blue cards).
As unfortunate as it is, sometimes we have to eliminate the source of our problems! Getting rid of the troublemakers although painful, is one way to help rid and curtail diseases; especially if you want to grow organically! Removing the varieties that are susceptible (prone) to diseases will help remove the source of infections and overall disease problems. This happened to us early in our nursery business and changed our outlook on what we grew there after! As we loved and grew some "Soel D'or" and "Persian Yellow" hybrid Rosa foetidas very prone to blackspot and more so in wet Nova Scotia climates! After continual sprayings of sulfur we came to the conclusion of roses that are really prone to disease should not be grown period! Especially if your a nursery that has to keep all its stock in top shape. You just can't win with varieties like these, as beautiful as they may be. Be sure to use dormant oil & sulfur the fall & spring after to eliminate all residues left in beds & other infected roses.
Spraying with broad-spectrum insecticides (those that are effective on ALL insects) reduce many natural predators that feed on the problem pests also. When you use these products you're wiping out pretty much ALL INSECTS where you have sprayed! This includes MR. Bee to the left! Population increases have been studied & noted on the occurrence of spider mites & thrips and the use of broad-spectrum insecticides on them. Reason, Not only are the natural Enemies of these pests killed, but also newer generations have built up a greater resistance to the insecticide and future applications will be less & less effective.
A strong jet of water from a garden hose can help control many diseases and insect pests. A direct stream to the tips where aphids are and the undersides of leaves where spidermites flourish will knock and keep these critter at bay. Aphids are very slow moving insects and the chances of those ones getting back on the plant is almost nil due to their predators on the ground and spidermites absolutely HATE WATER, so they won't hang around where they are constantly subjected to this. Because wet foliage encourages fungal diseases, it is wise to do this early in the day or on a windy day so leaves dry off readily. Never at night, if you can help it.
Blackspot, mildew & insect problems can be reduced by cleaning up and destroying all infected leaves early in the infestation, (Do NOT compost them) Good fall housekeeping is essential to not carry it on into next season. Clean-up all fallen leaves and leaves still on roses. Again don't compost these burn them if you can.

Botanical insecticides include rotenone and pyrethrum. Although these insecticides are derived from plants, they are not necessarily safe. In a well-managed garden, these should be used only when other methods have failed. They kill both beneficial as well as pest insects. They should be sprayed only at dusk when fewer honeybees are active; rotenone and pyrethrum are toxic to fish and should not be applied near ponds. Rotenone is an insect stomach poison best applied as a 1% solution in water. Pyrethrum is a nerve poison and paralyzes insects on contact. Nicotine, another botanical insecticide, is best not use it is very highly toxic to mammals.

Organic sprays and dusts include insecticidal soap and diatomaceous earth. Both are effective against soft-bodied insects such as aphids, spider mites, and some caterpillars. Insecticidal soaps penetrate insect membranes, causing paralysis and starvation. Use soft water when mixing and add isopropyl alcohol (2 Tbsp. per liter). Diatomaceous earth is a dust composed of the fossilized skeletons of microscopic sea organisms. The individual particles are sharp and cut insect bodies, causing them to dehydrate and die. It is applied as a dust, or in a water solution. Homemade sprays of ground up garlic and hot peppers can also effectively repel some insect pests.
Cultural and mechanical practices involve handpicking insect pests when they are few in number and crushing them underfoot, keeping the yard and garden free of decaying refuse, rotating the position of crops each year, and maintaining healthy plants with fertile soil.

Bacillus Thuringiensis, "BT"

Bt (Bacillus thuringiensis) The Natural Insecticide Bacillus thuringiensis(Bt) is a naturally occurring, soil borne organism that is used for its ability to control certain insect pests especially larvae of flies and months that can severely damage roses and other plants. Bt works in a natural, environmentally friendly manner. Bacterial agents, like Bt, are effective in controlling insects in the larva stage only. In this stage the larvae is usually a caterpillar or worm and to effectively control the pest, you must get it early at this stage both to eliminate the pest and to avoid too much damage to the leaves of the rose. The Bt is applied to the foliage of plants infested with a leaf or needle-eating larva. It is not as important to completely saturate the leaf surface as with insecticidal soaps as the larva need only eat a portion of the leaf with the bacteria on it to do the trick. You'll usually find these critters on the undersides of leaves and usually the same color as the leaf as not to attract their predators therefore Bt should be applied to the UNDERSIDES of leaves.
Bt is also broken down faster in sunlight. Application to the undersides of the leaf surfaces will prolong Bt's activity. High temperatures do not encourage Bt's breakdown.
After Bt spores are ingested by larvae, they grow and reproduce, meanwhile producing crystalline toxins. The crystalline toxins paralyze the digestive tract of the larvae causing it to cease eating. Death will follow, but time of death can range anywhere from 12 hours to 5 days after ingestion This depends on the amount of Bt ingested, the size and variety of the larvae and variety of Bt used for control. There are different strains or varieties of Bt available that have been selected for the control of specific insects. The one we promote for roses is Bt variety kurstaki (BTK). This controls the European corn borer, tomato hornworms, fruitworms, cabbageworm, cabbagelooper, spring and fall cankerworm, spruce budworm, and other caterpillar-like larvae. Other Bt varieties like San Diego (BTSD) controls early larvae of the Colorado potato beetle and Bt variety israelensis (BTI) controls mosquitoes, black flies and fungus gnats.

(ii) Using it on vegetables, Bt can be used right up until harvest, which allows for a longer-term control as compared to other insecticides requiring a waiting period from time of application to time of harvest.
(ii) There is no waiting period from time of application before re-entering the field.
(iii) Ficial or non-target insects are not harmed. (iv) Insects that ingest the Bt and later die from it are not dangerous to birds or other animals that may feed the dead insect.
(v) Is not known to cause injury to plants on which it has been applied and is not considered harmful to the environment.
(vi) With any substance you should not depend and use only it as insects tend to build up resistancy over time to them and for the most effective use try to use other means also every now and then.

Organic Earwig Control

Earwigs can really be a menace and to know how to effectively control them organically you must first know their life cycle. Here in Canada the earwig over winters as an adult in nests that is made in cracks and crevice, under rock and boards around the yard. The female lays a portion of her eggs in the fall. In the spring she will finish laying her eggs in the nests she has created. In late March to April, depending on how warm it gets, the males leave the nest. This is why early in the year one will see a few large earwigs. The female will remain in the nest and care for the eggs and the hatched young until late June to July. At this time the young earwigs and the females will leave the nests looking for food. This is the time of year when most people find that earwigs are a problem. This then is the time to focus on controlling them.

Try to confirm the life cycle with your area Dept. of Agriculture knows about when the females open up the nests. The most effective way to control earwigs without insecticides is the use of trapping. Again knowing the insects habit makes the use of traps fairly effective. Earwigs are night creatures. They feed and move about in the dark. During the daytime they will find areas to hide from the light. Any small crevice or container makes great daytime homes. Traps should be set in the evenings and collected in the morning to remove the captured insects. The best types of traps that seem to work well are: corrugated cardboard; Rolled up magazines or newspapers; small cans with openings punctured in the ends.

Make sure holes are large enough to let the earwig in. tubing such as bamboo rods. Two pieces of wood with groves cut and taped together. When collecting the traps, make sure they are collected each day in the mornings. Dispose of the earwigs in a container of diesel fuel or gasoline. This will kill the insects quickly. When placing traps, make sure they are placed in and under shrubs and other dark hiding places that the earwigs would like to stay. Place the traps when the nests are opened up later in the summer. People that report failures with traps result from setting the traps too early. They operate the traps and find that no or very few earwigs are caught. They then stop trapping and when June/July comes earwigs by the "hundreds" are found and they think the traps were not successful. "Wrong" just poor timing and not working along with the earwigs life cycle.

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