October Gardening Tips and Tasks

• Practice conservation gardening to support native wildlife through the cooler temperatures. Not all animals migrate to avoid the winter weather, some animals overwinter (spend the winter months in one of their life stages) here in Maryland. Many of these animals, including pollinators and beneficial insects, require plant debris like leaves, pithy woody stems, and flower stalks as winter habitat. To learn more about creating overwintering habitats in your greenspaces, check out this Fall Actions for Conserving Beneficial Insects (PDF) handout, this webinar on To Rake or Not to Rake, or one of our many Maryland Grows Blog posts about supporting pollinators in the fall and winter.
   
• Trees have so many benefits! They provide shading, cooling, wildlife habitat, carbon storage, and stormwater absorption. Maryland is aiming to plant 5 million native trees by 2031. Plant your own tree, volunteer to care for one, or support forest conservation. Be a tree steward!

• Flower buds are forming or are already formed on spring-flowering shrubs. To prevent reducing next year’s blooms, don’t prune spring-flowering shrubs like azaleas, rhododendrons, lilacs, hydrangea (bigleaf and oakleaf), and forsythia now. Wait until after they bloom next spring.
   
• Nursery stock trees and shrubs can be planted until the ground freezes. The earlier in autumn they are planted, the better for establishment. Don't plant evergreens (conifers or broadleaf) late in the season because they're at greater risk of winterburn.
   
• Carefully examine trees and shrubs prior to purchase to assess quality. With balled and burlap stock, cut the twine around the ball and cut away the nylon or burlap wrapping.
   
• Never carry a tree by its trunk, this can damage the roots. Instead, always carry them by their root ball or by the container.
   
• Fall coloration on white pines happens every fall but in some years it is more noticeable. The inner needles turn yellow and drop off. This can also occur on rhododendrons and other evergreen shrubs. This is normal for this time of year

Beneficial

• Yellow-faced bee adults are active and foraging for nectar and nesting habitat. Ensure your landscape has late season blooming flowers to provide nectar. This bee species likes to nest in hollow plant stems. If pruning perennial stems, consider leaving at least 8-24" of stem for nesting habitat. If you need to prune, consider gathering your trimmings into a pile and leaving them outside, allowing any overwintering bees/insects to still emerge come spring.  
   
• Black swallowtail butterfly caterpillars are active and preparing to form chrysalises, where they will spend all winter. Learn to recognize these caterpillars and consider tolerating their feeding damage. These caterpillars like to feed on plants in the carrot family, Apiaceae (carrot, parsley, dill, etc.). 
   
• Syrphid fly adults and larvae are active. Syrphid fly adults are seeking out nectar and the larvae are feeding on a wide range of soft bodied pests. Depending on the species, some syrphid larvae will start seeking shelter in leaf litter for overwintering habitat. Consider leaving some leaves as habitat, especially under flowers you have spotted syrphid larvae.
   
• Praying mantis adults are active and laying egg cases (ootheca). All mantid species in our area are considered beneficial predators (do not target and kill non-native mantid species). Support these predators by leaving their egg cases be, outdoors. Do not bring egg cases indoors during the fall and winter months, as the warm temperatures inside your home could cause an early emergence of immature mantids (allow them to naturally emerge in the spring).
   
• Florida predatory stink bug adults are active and feeding on a wide range of insect pests. These predators will start searching for overwintering habitat such as wood piles and sheltered crevices. Learn to distinguish this predatory stink bug species from plant-feeding stink bug species. Consider creating a wood/brush pile or leaving fallen logs to provide overwintering habitat.

Pests

• Spotted lanternfly adults may be found feeding on many host plants, especially tree of heaven (Ailanthus altissma). If you observe spotted lanternflies, inform the Maryland Department of Agriculture (MDA) by reporting the sighting on their website. These insects are mainly nuisance pests in residential gardens and landscapes. They have not been shown to significantly damage otherwise healthy ornamental plants. Consider sustainable management options if you want to take action. Adult spotted lanternflies will begin laying eggs on tree branches and trunks, and just about any outdoor surface (outdoor furniture, tires, etc.). You can remove egg masses by scraping them off into a container of soapy water or alcohol (ensure you properly identify the egg mass before removal). 
   
• Various types of caterpillars may be found feeding on the leaves of trees at this time of year. Research has shown that this late-season damage is minor to overall tree health and management of caterpillars is usually not necessary.
   
• Fall webworm caterpillars are active and create tent-like webbing on the ends of woody plant branches. Caterpillar feeding damage is usually minimal and control is not typically needed; caterpillars are typically only active through October. Tents can be pruned out or left for natural predators (birds) and parasitoids. Do not try to burn any webbed tents. Contact a professional if you would like to prune out a tent you cannot reach safely.
   
• Large milkweed bugs are active on their primary host plants, milkweeds (Asclepias spp.). No control is necessary unless you want to save the milkweed seeds. These bugs are primarily a nuisance pest and are only present on milkweed seed pods for a short period of time before they migrate south for the winter.
   
• Boxelder bug nymphs and adults are active and may congregate on boxelder trees, mulch, or in sunny areas of buildings. Adults will seek shelter for the winter, possibly finding their way indoors. This insect cannot harm humans, pets, or buildings and does not significantly damage plants. Control is generally not needed. If found indoors, vacuum or sweep up the insects. 
   
• Mexican bean beetle adults are active and feed on the underside of legume leaves (lima beans, snap beans, etc.). Adult beetles will spend the winter months in plant debris. Pull up and bag infested legume plants after harvest. Watch this short tutorial on how to harvest and bag bean plants.
   
• Many different cabbage-feeding caterpillars and moths are active. Check host plant leaves (mainly crucifers and brassicas) for signs of feeding damage and for the presence of caterpillars and caterpillar droppings (frass). Found caterpillars can be removed and destroyed. Remove infested plant debris after harvest to remove pest overwintering sites. 
   
• Striped and spotted cucumber beetle adults are active and chewing holes in leaves, flowers, and fruit. Common host plants include cucurbits, legumes, and tomatoes. Adults spend the winter months in plant debris and soil. Remove infested debris after harvest. In the fall or spring, lightly till the soil to disrupt soil-living life stages.
   
• Many different social wasp species, like yellowjackets, will seek out sources of sugar this time of year. Keep outdoor food and beverages covered, rake up and discard fallen tree fruit, and equip trash cans with tight-fitting lids. Certain wasps may sting if they feel threatened. Avoid swatting or handling any wasps. 

• Stop feeding your fish in outdoor ponds. They cannot metabolize food easily during cold weather.
   
• Black rat snakes may still be hatching in October. These harmless baby snakes are not black at hatching but are a light gray with dark brown rectangular markings down the back.
   
• Feeding deer is not recommended. The practice upsets the size of the local herd, increases their tendency to become pests, and may contribute to the spread of disease within their population.

• Full-size green tomatoes can be picked before a frost and brought indoors to ripen. They ripen more quickly if placed in a paper bag with a banana or apple. The ethylene gas released from the fruit will help to ripen the tomatoes.

• Carrots can be over-wintered in the garden by covering the bed with a deep straw or leaf mulch. Pull carrots through the winter as needed.

• Lettuce, spinach, arugula, and kale can be planted through the middle of the month. Cover these late plantings with a cold frame, temporary greenhouse, or row cover. Be sure to fertilize seedbeds, keep the soil moist, and protect seedlings from pests. The young plants will go dormant and re-grow in spring.
   
• Discard badly diseased plants and fruits; don’t till them back into the soil. All other plant waste can be hot composted.

• Start a compost pile by mixing together spent plants, kitchen scraps, fallen leaves, and grass clippings. Shred your materials with a lawnmower or string trimmer to speed up the breakdown process. Keep twigs, branches, and other woody materials out of the pile.

• Goldenrods and asters are important fall flowers for pollinators. Consider adding one or more of these to your garden. There are many species and cultivars available.
   
• Save seeds from annual and perennial flowering plants like zinnias, cosmos, celosia, and butterfly weed to be planted next spring.
   
• Geraniums can be overwintered in several ways. Entire plants can be brought inside and grown in a sunny window, or cuttings can be taken from existing plants. Cuttings from other annuals like begonias, salvias, and coleus also root well.
   
• Daffodil bulbs, alliums, and other spring-flowering bulbs can be planted now. Plant them in a sunny spot, in well-drained soil. Tulip bulbs should be planted from mid-October through November to prevent them from sprouting prematurely.

• Time is running out for lawn renovation or overseeding. Grass seed should be planted by the middle of the month.
   
• There is still time to apply fertilizer on your lawn. Look for a fertilizer with zero phosphorus. Apply according to the University of MD Extension lawn fertilization schedule. Fertilizer needs to be applied before November 15th to comply with the Maryland Department of Agriculture lawn fertilizer law. 
   

• In the cooler, sometimes wetter fall weather harmless toadstools and other mushrooms may be plentiful around tree root systems. However, destructive wood-rotting organisms produce conks on tree trunks. Affected trees may be suffering from extensive wood decay and should be inspected for trunk soundness by a licensed arborist.

• Inspect new indoor plants before purchase. Choose plants that appear to be free of insects and disease and have healthy foliage. Slipping the plant out of its container to look at the roots is recommended. Roots should be firm (not mushy) and able to hold the soil together without being too root-bound.
   
• If natural light from a window isn't bright enough, consider using grow lights to provide enough light to support plant health.

• Crickets, multicolored Asian lady beetles, boxelder bugs, stink bugs, cluster flies, and other innocuous insects may attempt to enter your home this fall to overwinter. Caulk, weatherstrip, and seal up all cracks, and entry points around your house foundation, vent openings, windows, and doorways to prevent these critters from coming indoors.
   
• Many different spiders like jumping spiders, yellow house spiders, wolf spiders may enter homes. They can wander indoors through or around windows, doors, and cracks. Caulk cracks and tighten up around doors and windows, especially those at ground level. Most spiders are shy and harmless to humans. Normally, they will not attempt to bite unless accidentally trapped or held. They are beneficial by feeding on nuisance insects. Killing spiders should be avoided, if possible.
   
• Drain flies are found primarily in rooms or areas where there are drains such as kitchens, basements near floor drains, etc. Drain flies are small, 1/16 to 1/4 inch long, delicate and fuzzy. Their fuzzy wings make them easy to identify.
   
• House mice and sometimes field mice may be more noticeable around and in homes due to the onset of cool weather. Keep grass and weeds properly mowed around your house and seal all cracks.