June FAQs

Annuals:

Q – What is that shiny golden bug feeding on my Sweet Potato Vine and Morning Glories?
A– This is Golden Tortoise Beetle, and one of its preferred foods is the genus Ipomoea, which includes these plants. Control: Any spray good for beetles in general, such as Eight or Captain Jack’s Deadbug Brew.

Q– I just planted some annuals and now they are all dead. We did not have a frost.
A– There are two likely possibilities. If the weather has been cool and damp in late May/early June, the soil has not warmed up enough for warm-weather annuals like basil and cucumbers, and they often die in cold soil. Also, if we have warm (and especially windy) weather, new plants with small rootballs have not had time to root out in the soil and will dry out very quickly. One day without water under these conditions is enough to kill small plants.

Bulbs:

Q– What should I do about those ugly leaves left over from my spring-flowering bulbs?
A– Do not cut or braid the leaves. Let them die back naturally. When they are mostly brown, then you can remove them. Mow around them, plant perennials or tall annuals around them, but leave the foliage in place—the bulbs need it to make flowers next year.

Q– When can I divide and move my bulbs?
A– Technically, you can move them anytime. However, the best time is after the bulbs are dormant and the leaves have died back, so that the leaves can nourish the bulbs as much possible while they are still green. In the new location, enrich the soil with organic material (not fresh manure) and a granular fertilizer like Bulb-tone™.

Containers:

Q– How often do I have to water my hanging baskets or other containers? Why are my containers drying out so fast now? Would SoilMoist added to the soil cut down on watering needs?
A– On a hot, windy day, water thoroughly at least once a day. In cooler or cloudy weather, they may go a few days without watering. Do not overwater or keep the soil soggy. The soil needs to dry out a bit between waterings, but not to the point of wilting. Remember that wilting can also be caused by too much water, so adding more water to wilted plants may just compound the problem. Use two methods to test whether a container needs water: put your finger in the soil to see if it is moist, and lift the pot to see if it is heavy (plenty of water) or light-weight (dry). Container-grown plants start needing more water in summer, because the light levels are higher and the air warmer. Also, because the plants have grown larger, leaf volume is much greater, so the leaves are giving off (transpiring) more water into the air. Remember that plants in a clay pot will dry out more quickly than in a plastic pot. Also, lush leaves (like impatiens) will dry out more quickly than succulent leaves (like portulaca). SoilMoist is a polymer that holds water. It does help retain moisture in the soil so that plants can be watered less frequently. Follow package instructions. However, it is not advised for plants like Rosemary or Portulaca that need good drainage, or during long periods of rainy weather (which can’t be predicted at planting time, of course).

Herbs:

Q- Why do my basil leaves have holes in them?
A– Almost certainly, these holes are caused by slugs feeding at night.  Sluggo is a safe product that we recommend for slugs and snails.

Q– How long do I have to wait to harvest my herbs?
A– Except for seeds like caraway, harvest herbs anytime the plant is big enough to withstand having some shoots removed. Most herbs taste best if harvested before they flower.

Lawns:

Q– What should I do for my lawn now?
A– Water enough to equal at least one inch of water per week (combined rainfall and watering). Raise the mower blade height in hotter weather, since longer grass will keep the roots cool. Avoid nicking the bark of trees and shrubs with the mower or trimmer, as this can cause severe damage to the bark and possibly death of the tree or shrub.

Perennials and Vines:

Q– Why are my bearded iris leaves dying? (Later in month) why are some of the rhizomes mushy and smelly?
A– Probably you have an infestation of iris borer. Squeeze leaves that have been chewed, to kill any larvae still inside. Kill any that you find in the rhizomes. In the fall, remove all iris foliage from your property.

Q – What is causing the holes in my Hosta leaves?
A – Probably slugs or snails. See Information Sheet. Also, we recommend the product Sluggo™.

Q– Why is my clematis wilting?
A– A disease called clematis wilt may be at fault. Consult with the Nursery Dept. for current recommendations. However, tiny tears in the stem caused by high winds may be the cause. Cutting back the stems may be enough and the plant itself can be saved, if not this year’s flowers.

Q– What is that bright red bug/What is defoliating my Asiatic and Oriental lilies and fritillaria?
A– Look for red eggs under leaves, black fecal matter, a yellow-brown to orange red larva, or a bright red bug. See handout on Lily Leaf Beetle. Spraying “Eight” or neem oil works well.

Roses:

Q– What should I be doing now to care for my roses?
A– Deadhead the blooms as they go by, use preventive sprays regularly according to package directions, and water regularly. When cutting roses, cut just above a leaf that has five little leaf parts, to encourage the formation of more bud-producing shoots.

Trees and shrubs:

Q– When should I prune my evergreen shrubs and trees?
A– Prune when new growth is partly unfurled.

Q– When should I prune my flowering shrubs?
A– Prune spring-flowering shrubs like forsythia and lilacs after they have flowered. Do not prune summer-flowering shrubs like hydrangeas or smoke bush this late in the season, or you will sacrifice blooms. However, dead wood or bad branches may be removed.

Q– What is defoliating my crabapple trees and/or the trees in my woods? (Late June)
A– Gypsy moths. See handouts.

Q– How should I care for my rhododendrons and other flowering evergreens and azaleas?
A– Remove spent bloom clusters. Top-dress with cottonseed meal, or fertilize with acid fertilizer like Hollytone after bloom is finished.

Vegetables and Fruits:

Q- What is cutting off my vegetables at the stem and leaving the tops lying on the ground?
A– Cutworms. See information sheet.

Q– What is that soft, fat, reddish brown insect on my potatoes/eggplants/peppers?
A– Colorado Potato Beetle. See Information Sheet.

Q– Why are the leaves of my cole crops/root crops wilting?
A– See Information Sheet on Cabbage Maggots.

Q– How can I protect my ripening strawberries from pests eating them?
A– Lay netting or floating row cover over the plants to protect from birds and chipmunks. See handout on Strawberries for general culture information.

Q– How can I take care of my vegetable garden for best results?
A– Water daily while seeds are germinating and when transplanted seedlings are rooting into the soil. Water the equivalent of 1” minimum per week unless we get that amount of rain. Thin new plantings of direct-sown seeds as they emerge. Fertilize regularly. Remove weeds while they are still small.

Q– What is that yellow & black striped bug on my cucumbers and other cucurbits?
A– See handout on Cucumber Beetles. Organic treatment: Japanese Beetle Killer with pyrethrin, Capt. Jack’s,  Rotenone Pyrethrins, Rotenone dust. Next year, cover with floating row cover until the female flowers (flowers with a swelling below the base of the petals) start to form, then remove the cover so flowers can be pollinated. The beetles’ cycle will be mostly over by then. In fall, clean up all weeds and refuse and do not compost any cucurbit vines that were affected.

Timely tips for June:
• Spread Sluggo™ to control slugs and snails.          

• By the end of the month, start preventive spraying for powdery mildew on Phlox, Monarda (Bee Balm), or other susceptible plants. Use a fungicide that lists this disease as a target.
• Start preventive spraying with a fungicide on Nonstop and Hanging Begonias. This will help prevent Botrytis in hot, moist weather, which will cause whole branches to drop off the plant.
• Prune hedges, especially evergreen, through mid-July. Prune spring-flowering shrubs after they bloom.                                                          

• Prune early-flowering shrubs that have gone by.                                      

• Water lawns and all new plantings so that they receive (including rainfall) at least 1″ of water per week.                                                                  

• Watch for pests and diseases and treat them early.                                  

• Cover members of the cabbage family with row covers to prevent cabbage worms.