bumble bee on a purple coneflower
Updated: June 27, 2024

Outdoor yard and garden tips

Sustainable Gardening

  • Take part in Pollinator Week! This is an annual celebration of the importance of pollinators and the many ways we can support them in our gardens and landscapes. Look for local events and consider participating in the National Pollinator Week Bioblitz through iNaturalist.
  • Reduce and compost food and yard waste. About one-third of all food produced never gets eaten. Food waste dumped in landfills generates climate-warming gasses as it decomposes without oxygen. Making compost at home is a solution.
  • Weeds are easier to manage when they are young and small and the soil is slightly moist. Hand-pull weeds or use other methods to manage weeds without chemicals.

Trees & Shrubs

  • Monitor newly-planted trees and shrubs for watering needs until they become established (for about 2 years), especially in the summer and fall. When needed, water deeply by allowing the water to soak into the soil directly underneath and around the root ball. Check the depth of water penetration into the soil by digging a small hole after watering. It should be moist about 6 inches down. A 2-3 inch layer of mulch is helpful to retain soil moisture. Keep mulch away from the trunk or stem.

Edible plants

  • Perpetual spinach, Malabar spinach, leafy amaranths, sweet potato leaves, 'Tokyo Bekana’, and Swiss chard are good heat heat-tolerant greens for Maryland.
  • Flea beetles are a serious pest of eggplant and also feed on potatoes, tomatoes, and members of the cabbage family. Row covers are an effective means of management but should be removed when plants flower to allow for cross-pollination by pollinators like bumblebees. Spraying plants with “Surround” (kaolin clay) creates a white particle film that can minimize flea beetle feeding. You can also control flea beetles with organic insecticides like neem (will require 2--4 applications) or spinosad (toxic to bees).
  • Young tomato plants may be exhibiting symptoms of various leaf spot diseases such as septoria and early blight. Remove badly infected lower leaves, keep a thick organic mulch around plants, irrigate at the base of your plants, and remove the lower 3-5 leaf branches to improve air circulation around plants.
  • The “June drop” of excessive fruits (especially peaches) is a natural thinning phenomenon that is more pronounced where no hand thinning has occurred. Hand-thin fruits on plum, peach, apple, and pear trees, leaving space (the width of one fruit) between the remaining fruits. Disease and insect problems, environmental stress, and lack of pollination or fertilization can also cause fruit drop. Pick up and throw out all dropped fruits.


  • Cut iris flower stalks down to the crown when they are finished blooming. Leave the foliage alone. If your iris are overcrowded after flowering lift and divide them. Check rhizomes for iris borer.
  • Warm-season annual flowers like zinnias, sunflowers, and cosmos can still be started from seeds at this time.


Beneficial insects

  • Skippers are active. This group of butterflies (distinguished by their hook-ended antennae and rapid, skipping flight) is a part of our pollinator community. Some skipper caterpillar species rely on grasses for food. Consider planting a native grass like little bluestem (Schizachyrium scoparium) amongst a diversity of flowering pollinator plants to support all life stages. This will mean tolerating some chewing damage from caterpillars.
  • Great spangled fritillaries are active. Support this native butterfly and other wildlife by recognizing and conserving native violets like the common blue violet (Viola sororia). 
  • Sphinx moths are becoming more active and are day and night pollinators, depending on the species. When creating pollinator gardens, incorporate night blooming plant species like common evening primrose (Oenothera biennis).
  • Margined soldier beetle adults are active, aiding in pollination while they feed on pollen, nectar and soft bodied pests. Recognize and leave these beetles be for their beneficial services. Incorporate a diversity of flowering plants to support these pollinating and predatory insects.
  • Bee-like flower scarab adults are active and found on a wide range of flowers, consuming pollen, leaves and flowers. Luckily many of our native plants like magnolias have co-evolved over thousands of years with these beetle pollinators and can tolerate this minor feeding damage. Leave these beetles be when you see them and consider supporting their populations by adding a diversity of cup-like flowers like pawpaw (Asimina triloba) or dome shaped flower clusters like New Jersey Tea (Ceanothus americanus). 


  • Spotted lanternfly (SLF) nymphs (immatures) are hatching and will grow through four life stages (instars) through July. Be aware of what their different life stages look like. Report any SLF egg hatch / early nymph sightings to the Maryland Department of Agriculture. If SLF eggs or nymphs are found in high numbers, the recommended control approach is to destroy the SLF physically. SLF is not harming landscape or garden plants enough to justify the risks of using pesticides that could harm beneficial insects.
  • Wasps are becoming more active. Maryland is home to over one thousand wasp species and not all species are aggressive. Identify a wasp before considering it a pest (check out our identification guide) and be mindful of nest building wasps located in buildings and high traffic areas. Leave nests alone when you can and contact a professional pest control company for any nest removals. Avoid using any home remedies. 
  • Scale insects are typically best controlled during their vulnerable crawler stage (when their eggs hatch, the newborns are called crawlers). Some species of scale, like cottony camellia scale (Pulvinaria floccifera) will begin hatching this time of year. Monitor for crawlers, particularly on plants with a history of scale. Specific controls and timing are based on the scale species. Utilize UMD Ask Extension for identification help.
  • Aphids are becoming more abundant. Allow local predators like lady beetles and parasitic wasps to control the aphids. Avoid high nitrogen, quick releasing fertilizers as studies have shown these fertilizers can boost aphid populations. Horticulture oil can be used on heavy aphid infestations. 
  • Japanese beetle adults are active. Brush adults into a bucket of soapy water held underneath foliage or branches. The use of Japanese beetle traps near your plants is not recommended. Studies show that traps can attract more beetles to your landscape resulting in increased damage.
  • Boxwood leafminer larvae (immatures) are hatching within boxwood leaves and will begin to feed (mine) within the leaf. Infested branches can be pruned out and disposed of. For chemical options, with heavy infestations, contact a professional pest control company. 
  • Bagworm larvae are hatching out this month and constructing new bags. Look for the little bags moving around on evergreen trees and shrubs and be prepared to spray infested trees with the biopesticide, Bacillus thuringiensis (B.t.) between now and mid-July, following all label instructions. 
  • Mosquitoes are becoming more active and abundant. Patrol your yard for mosquito breeding sites. At least twice a week, check and remove water that may be standing in trash and recycling cans, flower pot saucers, children and pet toys, wading pools, tires, tarps, or plastic sheeting. Reconsider mosquito sprays/fogs that can harm beneficial insects. Fans can be used to deter mosquitoes from outdoor porches.
  • Ticks are becoming more active and can carry serious diseases that affect humans and pets. Wear light colored long pants, long sleeves, and close-toed shoes. Tuck pants into socks. Tuck shirts into pants. Use insect repellents (age dependent, check label for safe use), always AFTER putting on sunscreen. Shower and check for ticks after being outdoors.
  • Squash bug adults are active. Place floating row covers over any host plants (cucurbits) to exclude adults and prevent egg laying. Monitor for adults, eggs, and nymphs (immatures). Adults are great hiders, hiding under leaves and mulch. Leaves with egg clusters can be removed and destroyed. 
  • Squash vine borer moths are active. Wait to plant squash seeds until mid-June to avoid adult moth egg laying. Cover squash with floating row covers until they flower; remove them during flowering to allow for pollination. A collar of aluminum foil can be wrapped around lower squash stems to prevent egg laying. 
  • Cabbage looper and imported cabbageworm 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. The biopesticide, Bacillus thuringiensis (B.t.) or neem oil can be used with heavy infestations, following all label instructions.  


  • Apple scab and a number of rust diseases (cedar-apple, cedar-quince, cedar-hawthorn, Japanese apple, and pear trellis rust) are destructive diseases of crabapple in the landscape. They cause severe leaf defoliation by mid-summer if not treated. The best defense is replacing disease-prone cultivars with resistant selections available at garden centers.

Indoor plant and insect tips

Indoor plants

closeup of mealybugs
Photo: Peggy Greb, USDA Agricultural Research Service, Bugwood.org
  • Monitor houseplants kept indoors for mealybugspider mitesaphidswhitefly, and scale. If houseplant pests are a problem consider spraying with a labeled horticultural oil or insecticidal soap. If possible, move the plants outside before spraying and when dry, move them back indoors. Discard heavily infested plants.

Indoor pests

  • Pantry pests, like Indian meal moths, grain beetles, cigarette beetles, and carpet beetles may be found around windows trying to get out of your home. These pests can be swept up or vacuumed.  No chemical controls are recommended.
  • Other unexpected indoor pests like wasps, moths or beetles can be carefully relocated outside or vacuumed. Many insects are attracted to light in the evenings. Consider reducing or turning off outdoor lights and reducing indoor light by using blinds or curtains over windows. Check for openings or cracks in walls, windows (window screens) and doors to prevent entry points for insects and other pests. 

Have a question? Contact us at Ask Extension.