Help for Gardeners: How to deal with the rodent problem (Andrew Johnston / Chicago Tribune)

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.

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:

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.

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.

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.

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.

Sue Kittek is a freelance garden columnist, writer, and lecturer. Send questions to Garden Keeper at grdnkpr@gmail.com or mail: Garden Keeper, The Morning Call, PO Box 1260, Allentown, PA 18105.

Planting: Plant a final crop of snap or pole beans, radishes, and carrots. Plant or pot up summer bulbs and tubers such as dahlias, cannas, calla lilies, and caladiums. Replace spent containers of pansies with heat-loving annuals. Move the pansies to cool shade and keep them watered during the summer if you want to keep them for the fall. Plant bare root trees and shrubs. Make sure the soil is dry enough to work — Don’t dig or plant in mud. Use annuals for containers, annual garden beds and to fill in bare spots in perennial or shrub beds. Shop for summer bulbs. Seasonal: Stalk tall flowers and provide supports for vining plants. Cut back boltonia by half the size of the plant. Cut Joe-pye weed back to three feet tall. Cut back candytuft to encourage bushiness. Shear back woodland phlox (P. divaricata)

Deadhead sea thrift (Armeria), centaurea, centranthus ruber, dianthus, fringed bleeding heart (Dicentra exima), hardy geraniums, bearded irises, red-hot poker (Kniphofia uvaria/tritoma), catmint (Nepeta), herbaceous peonies, oriental poppies, pincushion flowers (Scabiosa).

Fertilize Siberian irises, summer phlox (P. paniculata) and Shasta daisies with a light application of balanced fertilizer

Divide spring-blooming perennials after they finish blooming. Cut back peony flower stems as the blooms fade. Allow the greens to grow until fall then cut them back to the ground. Clip back iris flower stems as the blooms fade; divide plants in crowded beds. Pinch back helenium, chrysanthemums and asters to promote bushy growth and more flowers. Continue to pinch back new tips at two-week intervals until early July. Test soil for new beds, Retest soil in poorly performing areas or those that haven’t been tested in the last 3-5 years. Apply corn gluten-based weed control in the garden and establish a schedule for reapplication, usually at four to six week intervals

Lawn: Keep newly seeded or sodded lawns watered; supplement rain in weeks where less than an inch. By mid-June: Apply spring fertilizer treatments. Apply preemergent crabgrass control in the next few weeks. Fill in holes and low spots in lawn.

Chores: Harvest crops regularly, at least every other day. Check hoses; replace washers and correct leaky connections. Dump standing water and remove anything that may collect rainwater to help control mosquito populations. Check seed inventory for late crops and fall planting.

Inventory and restock seed starting and potting supplies. Clean, disinfect and store pots and trays used for seed starting and transplants. Water any recent plantings and containers anytime we experience a week with less than an inch of rain. Fix damaged screens and garden hoses. Repair damaged caulking around doors and windows. Dump standing water and remove anything that may collect rainwater to help control mosquito populations. Provide deer, rabbit and groundhog protection for vulnerable plants. Reapply taste or scent deterrents. Clean and fill bird feeders regularly. Clean up spilled seed and empty hulls. Dump, scrub and refill birdbaths at least once a week. Consider setting out nesting materials if you have them.

Clear gutters and direct rainwater runoff away from house foundations.

Tools, equipment, and supplies: Check spring equipment and supplies, repair or replace. Sharpen blades, get fresh gas, check and/or replace oil. Send mowers and tractors for tuneup or repair. Safety:

Clear lawns of debris before mowing and make sure pets, children and others are well away from the area being mown.

Store garden chemicals indoors away from pets and children. Discard outdated ones at local chemical collection events. Photograph storm damage before clearing or repairing for insurance claims and file promptly. Anytime you are outside and the temperatures are 50°F or warmer, watch for tick bites. Use an insect repellent containing Deet on the skin. Apply a permethrin product to clothing. Wear light-colored clothing, long sleeves, hats and long pants when working in the garden. Stay hydrated. Drink water or other non-caffeinated, nonalcoholic beverages. Even in cool weather, apply sunscreen, wear hats and limit exposure to sun. Wear closed-toe shoes and gloves; use eye protection; and use ear protection when using any loud power tools.