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DOUG’S GARDEN BLOG – “They’re Here!!!” Time to Protect Your Plants

By Doug Hensel
Doug's Blog

BE ON THE LOOKOUT FOR JAPANESE BEETLES BECAUSE THEY ARE HERE, OUT AND ABOUT, AND EATING AWAY

I was wondering when customers would be coming into the garden center with evidence of damage to their plants from Japanese Beetles. This past week I had a couple of customers right here in North Chesterfield needing advice as to what to do to protect their plants – both of these customers live in the Founders Bridge subdivision.

So, this year, the Japanese Beetles are truly a “June bug.” The term June bug isn’t a scientifically assigned name. Instead, it’s a common name applied regionally to a variety of different beetle species. One common species is the Japanese Beetle (cotinis nitida). Our Japanese beetles have a green body that measures up to an inch long. It is not aggressive and will not bite. They are clumsy aviators.

Now that they are here, they begin eating some of our favorite plants such as roses and tomato plants. While they are out and about, they will eat and will mate and will lay eggs.

STEP #1 IS NOW

Your mission to eliminate their damage to the plants as much as possible while they are flying around and to reduce their population. The best choice is to use a JAPANESE BEETLE TRAP system. You want to set the trap away from all your plants in a remote area. The bait inside the trap lures the beetle away from the plants and traps them inside the beetle bag. Check the bags periodically and replace them when full. Keep in mind that Japanese beetles will be around for a few weeks. As gross as this may seem, because Japanese beetles are not aggressive and are slow, you can spend some time with the plants and handpick these insects and toss them into a plastic bag. In addition to the trap system and handpicking, you can resort to sprays such as the Bonide’s CAPTAIN JACK’S DEAD BUG BREW. Captain Jack’s is made with Spinosad, which is good for organic gardening and is not harmful to our beneficial insects when used correctly and at the right time of day.

STEP #2

While the beetles are flying around and mating, the female will lay eggs on plants. In August, these eggs will hatch into larvae that will move to the soil. This larvae stage of the Japanese beetle is the white grub worm. So, as STEP #2, in September, you want to apply a grub control product in order to kill as many of the white grub worms as possible before they move deep into our soil for the winter. There are many very good grub control products. My favorite is MILKY SPORE. Milky Spore is an environmentally friendly product. The grub worm will ingest the milky spore and die, and, at the same time will help multiple the amount of milky spore in the soil for even more control.

STEP #3

Sometime in February or early March, you will want to reapply your chosen grub control product. It is at this time that the white grub worm starts to surface and will eat on grassroots, thus damaging the turf.

From an educational angle here is the life cycle of the Japanese beetle which is important to know in conquering your battle with Japanese beetles:

  • Right now the beetle is eating and mating.
  • The female beetle will lay her eggs in the sunny areas of healthy grass.
  • These eggs will hatch within four days after being laid.
  • It’s these eggs that are white grub worms
  • While in this white grub worm larvae stage, they will eat roots of the lawn. They will stay in the soil eating until later this fall when they must burrow down below the frost line to avoid being frozen.
  • In the fall the white grub goes deep in the soil and will emerge in the spring once our soil warms.
  • Then the white grub worm turns into the Japanese beetle sometime in late June.

Good luck and come see us for more information and for supplies.

To read more posts from Doug, visit our blog

17 thoughts on “DOUG’S GARDEN BLOG – “They’re Here!!!” Time to Protect Your Plants

  1. My apple trees branches are becoming black like some disease going onto them.
    I would like to know any product good as a remedy to it.

  2. Salah,
    From your description it may be what is called ‘sooty mold’, which is a fungus. If you can reach a couple of these branches to inspect for any insects, such as aphids. Aphids secrete a sticky substance that this mold attaches to. If I am correct then you want to treat the apple tree with a safe product such as Neem. Or, if the tree is small enough you can spray the tree with a soap and water solution. Good luck. I hope I am right.

  3. Bonnie,
    Good Afternoon. Thank you for sending me your gardening question.
    How long have you had them? My first thought is that your hosta plants are stressing out in this heat. How much direct sun are the hostas receiving? Too much sun can cause these symptoms. Let me hear back from you. Doug

  4. Hello
    I’m having trouble with my Petunias. Husband and I planted on both sides of our walkway. One side is fluffy and beautiful, the other side looks bad.
    I thought that the squirrels were getting into them. We replaced them 3 times with no success.
    It just looks like something has come into the middle of them and smushed them. We water often, this is my first year with this problem. HELP!

  5. We extended our garden this year to incorporate more tomato plants. We fed them and they immediately grew strong with lots of blooms. Now we have lots of green tomatoes but unfortunately some are turning black on the underside. It doesn’t scratch off and we have not had any issues with tomato pests (yet). I’ve plucked the diseased tomatoes but would like to know how to treat this problem and not lose our harvest. I’m dying for a tomato sandwich! Thank you for your time.

  6. Bethanne,
    Happy Friday. From your description what you have going on with your tomato fruit is called BLOSSOM END ROT. Blossom end rot occurs on the fruit when the soil is lacking calcium. What also can enhance blossom end rot is inconsistent watering – plants going dry between waterings and staying too wet with the watering. If you can find any ESPOMA TOMATO TONE this product is loaded with calcium and is a good, organic all around food for the plants. Unfortunately, we have been sold out of Tomato Tone for weeks and our suppliers are out as well 🙁 . Any of the fruit that has the black bottoms you should go ahead and pick off the plant. No need for the plant to put any more energy into growing these damaged fruits. Doug

  7. Jacqueline, Happy Friday. Is the sunlight equal on both sides of your walkway? Is the soil identical? Petunias are strong sun lovers. More sun the better. And, they like to dry a little between being given a thorough watering. How about feeding? Flowering annuals like to be fertilized on a monthly basis. And, this is a good time to trim them back and feed. They will then produce new growth and eventually new flowers.

  8. Your comments seem to be spot on, Doug.
    Love the Q&A.
    Do you still have a journal?
    On another note, Doug, do you give presentations to garden clubs? I would love to have you speak to Dominion Valley Garden Club. Our meetings are held at the Fairfax Station Railroad Museum. Please let me know.

  9. Michelle,
    Happy Friday to you.
    As for gardening presentations… I live in the Richmond area and I will talk to different garden clubs in this area. Now, this year is different because of the pandemic that we are all experiencing. I have not committed to any presentations this year. And, until things turn around and become more safe I am not scheduling any outside activities at this time. I want to personally thank you for reading my various blogs and to thank you for this kind invitation to come up to Northern Virginia and speak to your club.

  10. Doug, thanks so much for your quick reply. Would you consider, perhaps, joining a zoom meeting in the fall?
    Have a great weekend.

  11. Lake house (Lake Gaston so 80 miles south of RIC) has 6 large crepe myrtles, all being eaten by Japanese beetles. The 2 near the back deck are SPECKLED with black (mold-like) dots on their leaves plus the composite decking closest to both plants. Is this some type of bug debris? If so, how do we eliminate this on both the plant leaves and the decking? Mega thanks!

  12. Kris,
    Good Afternoon. Japanese Beetles are out and about eating away. Crape Myrtles are one of their favorite plants to eat upon. The beetles will be around for a couple more weeks so more damage will occur if you don’t try to curve the damage now. Japanese Beetle traps do a great job in capturing beetles and drawing them away from your plants. The other problem you are mentioning is a fungus issue. Now that we have turned hot and humid, fungus on crape myrtle trees is common. A good, general fungicide will help. Daconil, Copper fungicide, Infuse are all good products to correct this fungus problem. Good luck. I know it is frustrating. Doug

  13. I planted a young redbud tree in my yard in early Spring. One by one the branches are dying. The leaves are turning light tan, then copper color. I started using a watering donut but not sure if that is the problem. Any ideas on what is happening?

  14. Anne,
    Good Afternoon. As long as you planted it “hundred dollar hole for a ten dollar plant” theory, then it could come down to the Redbud tree just trying to acclimate to its new environment. Glad to read that you are using a watering donut. this is a great device to assure good, deep, thorough watering for the root system. This using the donut for the rest of the summer and into the fall. We are hot and dry at this moment – typical “dog days of summer” with heat and dryness. Bottom line, let’s hope the tree turns around. Keep me informed periodically. Thanks

  15. I have several Bouganvilla plants kept indoors. They have done very well and have had almost constant blooms for the last 2 years. This yr the leaves are discolored , speckled yellowish and then the tips of the plants with new blooms turn dry and blackish . What is wrong with the plants and how can I make them healthy again.

  16. Tariq,
    Sorry to read you are having trouble with your Bougainvillea plants. Be sure to check the foliage closely for any insect damage, such as mites. Speckled leaves leads me this think that this may be the cause. If so, you can give the plant a good Ivory Soap and water bath by carefully washing each leaf – both top and bottom. Also, have you recently re-potted these plants? If so, then the additional soil could be keeping the plant too wet for too long of a period. One thing that I have learned about Bougainvillea plants is that letting them dry between waterings and stressing them a little is what forces the plant into bloom. Let me hear back from you if I an on track to help you get these plants to recover. Doug

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