Colder weather and shorter days are sure signs that autumn is here and winter will not be far behind.
At this time of year perennials, trees and shrubs begin the dormancy process. Plants will not put out any new growth and all their energy goes into the roots. Plants must store enough nutrients to insure they can break dormancy and begin growing next spring.
Perennials, trees and shrubs that are still putting out new growth will experience some or total winterkill as this growth will not have time to harden off before winter. For this reason horticulturalists recommend that people stop applying fertilizer at the end of July.
Weeds have similar cycles as the plants that we cultivate only weeds are hardier and less likely to winterkill. It is possible to take advantage of their dormancy preparation to remove them from the garden.
Applying herbicides chemical or natural at this time of year works well as plants are actively taking in nutrients and storing them in their roots. Once the pesticide is in the plants system it will move into the root and kill part or all of the plant.
Repeat applications might be necessary to eradicate all the weeds as some plants are less susceptible to chemicals than others.
When using pesticides; always read and follow the directions on the container. Pesticide containers should list target plants as well as any mixing instructions if applicable. For those that are unfamiliar with botanical terms, broadleaf weeds are plants with leaves that have one main vein up the center of the leaf and smaller veins break off from it. Leaves that consist of veins that run parallel, side-by-side are considered grasses.
Pesticides that are for residential use can be purchased; ready to use or in concentrated solutions.
Follow the directions because using more product is not necessarily better. Too much chemical in a mixture can cause the top growth to die and leave the roots intact. When this happens the plant produces new growth and continues to be a problem. Excess use of chemical will also leach into the ground water and eventually show up in lakes and rivers.
Apply foliar spray on herbicide on a calm, dry day. Tiny droplets of pesticide can be carried by the wind and damage other plants in the area. It is a good idea to cover susceptible plants that are close to the area being sprayed.
For the pesticides, chemical or natural to work it must be absorbed by the plant which means it must be in direct contact with the plant for a number of hours. For best results spray chemicals on a day when it is not raining. Using chemicals is controversial with some provinces and urban areas banning the use of cosmetic chemicals. Locally this has not become a problem but take close neighbors into consideration by not applying pesticides when they are enjoying their yard.
Not all gardeners use pesticides. Constantly pulling, cutting, digging and removing roots will eventually starve the plant.
Removing the tops at this time of year will disrupt the plants cycle making it weaker next spring.
Pesticides natural or chemical are effective poisons and should be used with care and consideration.
Linda Tomlinson is a horticulturist and educator living in Rocky Mountain House. You can contact her at your_garden@hotmail.com.