How to deal with rodent, mosquito problems
A few weeks ago, Randy asked for methods to deal with deer and rodents in the garden. I covered deer but not rodents at the time. This week I attack the topic of rodents and what a gardener can do about them.
First, exactly what are rodents? They are the second-largest group of mammals. The group includes the following rodents found in Pennsylvania: beavers, chipmunks, groundhogs, lemmings, mice, muskrats, rats, squirrels, and voles.
Other garden pests — rabbits, moles and shrews — are not rodents. However, for simplicity’s sake, consider these techniques appropriate for rabbits as well. I will not include beavers, lemmings or muskrats, as they are not serious, widespread garden problems and require very different techniques to control or exclude them from an area.
Possible exclusion techniques include:
Removing hiding and nesting areas in or near the garden. Brush piles, tall grass, crawl spaces under decks or porches, and uncovered compost piles. Mulches are a dilemma; while they restrict weeds, control soil temperature, and conserve moisture, they also provide cover and nesting areas for garden pests.
Restrict easy food sources such as bird seed spills or unsecured containers, any outside pet food containers, and control lawn grubs.
Fencing is a great option but is limited because of the work necessary to properly install a fence and the associated cost. Requirements for an effective fence include:
Chicken wire or similar wire mesh with small openings. The height must include three feet above ground and another 12 to 18 inches below the ground. Plus poles and clips to attach the fencing to the posts.
A trench, six to eight inches deep and wide, around the garden. This is to allow for placing an L-shaped section at the base of the fence facing outward. Place and bury the bent fencing to the posts, allowing the fencing to extend three feet above the ground.
There are electrical options including two wires placed at the base of the fence at the soil line, spaced two and four inches from the ground to deter entry at the base of the fencing.
Deterrents are another option but must be rotated as the pests become familiar with the source and learn that nothing happens. So, alter or move whatever methods you use to keep the pests guessing and wary of entering your garden.
Deterrent methods include:
Commercial products such as garlic clips, castor oil products, predator urines, dried blood products, and smelly taste deterrents. These must be reapplied regularly and after heavy rains.
Hot pepper powders are effective against rabbits and squirrels.
Motion-activated water sprays.
Reflective tape, aluminum pie pans and other bright items.
Heavily scented plants can provide some protection if planted around the beds use:
Mint: in pots to avoid spreading or dried and sprinkled around the garden.
Herbs: A border of herbs can provide enough scent to deter some pests.
Alliums: Onions, leeks, scallions, garlic and other members of the allium family.
Ornamental plants: Castor beans, marigolds and fritillaries.
Personally, I have had success with dried blood
for rabbits. Mint has worked well in indoor settings but I have not used it extensively outdoors. Castor bean plants in the yard are not only attractive but substantially decreased the burrowing of animals. Borders of the smelliest marigolds and herb borders have also helped. I tried the motion-activated sprayer and enjoyed the satisfying sound of it going off and the noise of scattering deer but it did not cover the entire area so was of limited effectiveness. None are totally effective but short of fencing, little is.
Mosquitoes
Everything seems to have a week and this week is National Mosquito Control Awareness Week according to the American Mosquito Control Association. Since mosquitoes are not only annoying but also disease carriers, we should do what we can to decrease their chances of feeding on us.
Breeding sites: Mosquitoes can breed in incredibly small amounts of stagnant water. Thus, we have to be diligent to dump standing water and remove unnecessary water-gathering hazards in the yard.
Empty and remove containers, empty garden pots, old tires, and any other garden debris that collects water.
Turn over wading pools and wheelbarrows when not in use.
Empty plant saucers regularly after watering or rain.
Drain, scrub and refill birdbaths at least once a week.
Clear clogged rain gutters.
In areas that can’t or shouldn’t be eliminated, regularly treat the water with dunks designed to kill mosquito larva — usually a product containing Bacillus thuringiensis israeliensis (Bti).
When outside, wear long sleeves and trousers as well as a good mosquito repellent, especially at dawn or dusk, prime feeding times for mosquitoes.
Foggers will work for a few hours and may be appropriate for outdoor gatherings.
In our garden
Our tomato experiment, applying micronutrient spray to some plants, has shown initial results. The sprayed plants are about a third larger and have more flowers than the unsprayed ones. I should mention that this soil is really good with a compost of manure worked in at the end of every season. My mandevilla, also sprayed, is blooming quite well and quickly growing despite being otherwise neglected. We’ll see how things progress as we have a mix of determinant and indeterminant tomatoes that will grow and produce at different rates over the coming months.