June
Monthly Garden Tips

June is a great time to finish planting gardens, containers and hanging baskets and then spend time relaxing on your deck, porch or patio enjoying the beautiful colors.  June is Perennial Month, and we experience the greatest concentration of perennial bloom during this month. It is an ideal time for outdoor entertaining and showing off your yard and garden when plants are fresh and growing at their best. The long days allow time for both gardening and socializing. 

General Tips    Shrubs & Trees    Annuals & Bulbs   Perennials    Veggies    Fruits
 The Lawn    Houseplants    Pest Control

GENERAL
GARDENING TIPS

• Memorial Day weekend marks a milestone for many gardeners.  They move from planning to planting, so if you haven’t finished, time is wasting. 
• To encourage good rooting of new plants in the ground, make sure you water long enough to moisten the soil around the root zone of the plant. Sprinkling a little water on plants every day can do more harm than good by encouraging the roots to stay close to the surface where they are susceptible to drying out faster. Stick your finger into the soil and if it's dry two inches deep, it's time to water. Apply enough water to moisten the soil a bit deeper than the root zone.
• Weed removal is important for a number of reasons. It conserves moisture, conserves nutrients in the soil and helps prevent the spread of disease and insects. It is important to pull the weeds before they have a chance to flower and go to seed.
• Use mulches to deter weeds and retain moisture in the soil  
• If a compost heap fails to heat, mix in green matter and manure to aid the decomposition process. We also recommend Bonide Compost Maker.
• Persistence is necessary to keep shallow birdbaths filled with water. If a deep tub or a fountain is used, add a few goldfish to keep the mosquito larvae under control.

SHRUBS and TREES

• Watering roses with soaker hoses or drip irrigation will reduce the spread of black spot disease. It is important to keep the foliage dry. This is not a problem with the Knockout series of roses.
• Use bark mulch around young trees to protect them from lawn mower damage.
• Spring flowering shrubs such as spirea, viburnum, lilac and forsythia should be pruned as soon as they are done blooming. Older stems can be removed to the ground and plants can be lightly shaped by cutting the longest branches part way back with a pruning shears.  This results in plants with a more natural look that will stay dense in the middle and bloom well again next year.  
• Mid to late June is an excellent time to take softwood cuttings of shrubs to start new plants.
• Roses will need to be fertilized  with Espoma Rose Tone each month through the summer
• Make sure your climbing roses are securely tied into position. Prune them after blooming.
• Fertilize flowering shrubs like Rhododendrons, Camellias and Azaleas immediately after they have finished flowering with Espoma Holly Tone a 'Rhododendron' or 'Evergreen' type fertilizer.
• Dead head the developing seed pods from your Rhododendrons and Azaleas to improve next years bloom. Be careful not to damage next year’s buds which may be hidden just below the pod.
• It's hedge trimming time.
• If your are thinking about planting some new roses, now is a great time to select your favorites, as they are coming into bloom and you can discover their colors and scents in person, rather than from the description on a label.

ANNUALS and BULBS

• For hanging baskets in cool, shady locations, use tuberous begonias, ferns, impatiens or fibrous rooted begonias in combination with trailing plants, such as English ivy.
• Remove old flower heads from annual bedding plants to keep them blooming. This task isn’t necessary for many of the new plant lines of sterile seeded plants. We would be most happy to point out these labor saving plants.
• As the weather dries out, your container plants may need daily watering especially if the pots are exposed to the drying sunlight. Fertilize weekly with Garden Elements Bud & Bloom Fertilizer or the organic Neptune Fish and Seaweed.
• Remove foliage from spring bulbs after it turns yellow and begins to dry. Set out bedding plants to cover the bare spots using care not to damage the bulbs. Once the foliage of Daffodils has died back, you may divide and move the bulbs to a new location. Daffodil clusters should be divided every 3 years to ensure good blooming.
• Pinch your Chrysanthemum's to encourage them to be bushier and have more blossoms. Pinch them again, every 6 inches or so, as they grow. Do not pinch after 15 July, or after you see flower buds form.
• Spruce up your front porch, patio, or balcony with a colorful container garden. Recycle any type of container that supports plant root growth and provides adequate drainage. Be sure to water your containers properly, allowing excess water to run out of the bottom.
• June is the month to plant dahlias, once all danger of frost has past.
• Choose a location with fertile, well-drained soil that gets at least six hours of sun a day. Dahlias like sandy or loamy soil, but will do fine in clay soil if you work in a two- to four-inch layer of well-rotted manure or compost a few weeks before planting. We usually have a nice selection of bagged dahlias.
• Harden off and plant seedlings of warm-weather vegetables and flowers
• Attract beneficial insects to your garden by planting a variety of flowering annuals and perennials that bloom over the entire growing season.

PERENNIALS

• Plant ground covers under shade trees that do not allow enough sunlight to grow grass. Vinca minor, Laimastrum, English ivy, ajuga, and pachysandra, are ground cover plants that grow well in shady spots.
• Ground covers such as vinca, pachysandra, carpet bugle, and dead nettle (lamium) can be divided and transplanted now to create new beds or enlarge existing ones. On a cloudy, cool day, use a sharp shovel or trowel to separate offshoots from mother plants and transplant them into a shady new location. Keep them well watered until established.
• Divide and transplant spring-flowering perennials, if needed, after they have finished blooming.
• Some perennial flowers such as Monarda and Artemisia are very fast growers and will take over your garden if they get a chance. Don’t be afraid to dig out parts of large clumps and share them with friends or put in the compost pile.
• Fertilize peonies with Espoma Garden Tone. For larger blossoms, pinch off the secondary flower buds as they form. Insert 2 - 3 foot long twiggy sticks near the clump's center to provide support to the developing stems.
• Grass can become a problem in perennial beds; as solution is High Yield Grass Killer. It is a herbicide that will kill grass, and not harm broad leaf perennials.

VEGGIES & HERBS

• Planting starts with preparation of the soil, including a soil test to determine the soil's pH, or acid level, and nutrient needs. Most vegetables prefer a soil pH of 6 to 7, which is critical in "unlocking" nutrients in the soil. Call Penn State Co-Op Extension to obtain soil test kits. 412-473-2540.
• Start any of the warm weather vegetables (Corn, Beans, Peppers, Egg Plant, Tomatoes, Squash, Pumpkins, etc.) as soon as possible.
• After your vegetable garden is well established, it is best to water it thoroughly once a week rather than giving it a light watering everyday. That way, a deeper root system is encouraged to develop, which will later help plants tolerate dry weather.
•  Keep a close eye on the quality of your spring crops. Hot weather causes lettuce to bolt and become bitter. Plant a warm season crop as soon as the spring vegetables are harvested.
• The best time to harvest most herbs is just before flowering, when the leaves contain the maximum essential oils.
• Left over vegetable and flower seeds may be stored in a cool, dry location for planting next year. One method is to place seed packets in a jar or plastic bag and store in a refrigerator.
• Mound the soil up around your potato plants. It does no harm to the plant if the soil covers the stem. Tubers near the surface which are exposed to sunlight will turn green and taste bad. As early potatoes begin to die back, reduce watering.
• Some vegetables like carrots, lettuce, and beets may require thinning after direct seeding. Thin enough to provide good air circulation (this prevents foliar diseases) and to avoid competition among plants for water and fertilizer.
• Tomatoes usually need support to keep fruit off the ground and keep plants healthier by promoting leaf drying.  Indeterminate varieties continue to grow longer vines all season. They benefit from suckering as well as staking. Remove suckers that sprout from the stem up to the first flower cluster. This will promote earlier fruiting and keep the plants to a manageable plant size.  'Celebrity' and other determinate varieties will not sprawl as much and do not require suckering.
• To reduce weeds and conserve soil moisture, apply a thick layer of leaves, hay, or straw mulch around vegetable plants, especially long-season crops, in mid-June.  Waiting until mid-month gives the soil time to warm up.  Avoid using weedy hay as mulch.
• All warm-season plants including tomatoes, peppers and melons can be safely planted in June.   If tomato plants are leggy they can be planted deeper and will root along the buried stems.
• Blossom end rot shows up as dark, sunken spots on the blossom end of tomatoes, peppers, and squash. It's caused by a calcium imbalance in the plant -- the soil may have adequate calcium, but the plant isn't able to take up enough to supply the rapidly developing fruit. To minimize the problem, keep soil evenly moist, apply a layer of mulch to conserve moisture, don't over fertilize (especially avoid high-nitrogen fertilizer), and avoid damaging plant roots while cultivating.
• Sow seeds outdoors of beans, okra, pumpkin, sweet corn, and watermelon. Plant only partial rows of beans and sweet corn so that successive plantings can be done every week or two. Sweet corn should be planted in paired rows for good pollination

FRUITS

• This is still an OK time to plant apple, pear, peach and all other fruit trees. Many fruit trees require two different varieties to pollinate properly. Be aware of this and ask one of our nursery professionals to guide you in selecting varieties.
• Apple trees are notorious for setting more fruit than they can support. Usually the tree relieves this burden by dropping some young fruit in what's called the "June drop," but you may have to thin in addition to this natural drop. Thin out small green fruits on apple, peach and plum trees to one every 6 inches on the branch so they can develop to their full size and sweetness.
• Prune suckers and water sprouts from all fruit trees.
• If you have a strawberry bed, harvest frequently and remove any berries that show signs of grey mold or rot diseases. These berries not only are inedible, they quickly spread the diseases to other ripening fruits. Pick and remove the rotten berries and mulch under plants with straw to reduce contact with the ground where the disease spores reside.
• Allow one or two runners to develop from the most productive strawberry plants.
• Remove the newly formed blueberry fruits for the first three years after planting in order to promote good plant growth

THE LAWN

• Lawns maintained at the correct height are less likely to have disease and weed infestation. Kentucky bluegrass and tall fescue should be mowed at two or three inches in height. Mow frequently, removing no more than one third of the blade at each cutting. Setting your mower for a higher cut during the spring months will help the grass to grow in fuller and help choke out the weeds.
• If the weather becomes hot and dry raise the cutting height of the mower.
• It's not too late to reseed or over-seed (spreading seed over areas of weak or spotty grass) the lawn. Be certain to keep newly seeded areas well watered.

HOUSEPLANTS

• Once the fear of frost is over, you can move houseplants outside to the deck or patio and enjoy them outdoors for the summer. They will benefit from some fresh air in a shady spot. It is best to gradually introduce them to more direct sunlight to prevent the leaves from being burned. Just make sure to bring them in if the nighttime temperatures don't drop unexpectedly below 40°.
• Feed your houseplants with a good quality indoor plant food such as Shultz All Purpose Plant Food, or Neptune Fish and Seaweed which is a natural fertilizer.
• Continue to watch for insect or disease damage. Bonide Systemic Houseplant Insect Control and Bonide Infuse Systemic Disease Control can eliminate these pest problems.
• If needed, re-pot root bound houseplants to a larger pot. Use Fafard’s Complete Container Mix when repotting houseplants.
• Hibiscus, Mandeville, Diplademia, and Jasmine are just some of the flowering tropical plants you can add to your deck, patio or balcony.

PEST CONTROL

• Identify garden pests before you attempt to control them. If you decide to use chemical control, read the label carefully.
• Slugs will hide during the daytime beneath a board placed over damp ground. Check each morning and destroy any slugs that have gathered on the underside of the board. An alternative would be to use granular products such as Bonide Slug Magic or Sluggo. Take steps to control slugs now, before they have a chance to reproduce and devastate your garden. Slugs are particularly damaging to hosta.
• Check your roses for mildew, aphid, black-spot or other insect or disease problems and if they appear take steps to control them right away. Bonide Rose Rx 3 in 1 provides an effective control for these disease problems and has an additional benefit of insect control. Bonide Liquid Copper Fungicide provides an organic disease control.
• Protect yourself, your family and your pets from contact with pesticides. Wear protective clothing, and spray only on calm days. Wash your hands and clothing thoroughly after using garden chemicals. Buy only enough to do the job; excess chemicals are difficult to dispose of properly.
• Everyone can incorporate integrated pest management (IPM) practices in their gardening. To reduce pesticide use, plant cultivars that are resistant. Use pesticides least toxic to fish and wildlife, and minimize drift when applying chemicals, especially around fish and wildlife habitats, by using low-pressure sprays and selecting nozzles that produce large droplets. Always follow the instructions on the pesticide label.
•  The best way to gain maximum benefits from predatory insects, such as lady bugs, is to maintain an environment that encourages their long-term, natural establishment near your garden. A mixture of crimson clover and hairy vetch used as a cover crop will provide the predators needed habitat while improving the soil. Switching to insecticidal sprays that break down readily will also help.
• To protect bees that pollinate many of our crop plants, use organic products and spray pesticides in the evening after bees have returned to their hives.
• Japanese beetle traps are probably not appropriate for most home use because they tend to attract the beetles without trapping them all. However, if traps are used, recent research indicates that white is more attractive to Japanese beetles than other colors. Place traps at least 25 feet from fruit trees and roses to lure the pests away from treasured plants.
• Lacebugs can be controlled on azaleas, and andromeda rhododendrons and other plants with Bayer Advanced Tree & Shrub Insect Control or Bonide Annual Tree & Shrub drench. It will take about 2 weeks for the soil applied application to be taken up by the plant and start its control.
• Watch for tiny, sap-sucking insects called aphids on roses, perennial flowers, shrubs and trees.  Many can be dislodged with a hard spray from your garden hose or 2 applications of insecticidal soap will usually greatly reduce any aphid damage to your plants.

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