Late summer in the garden brings beautiful flowers, foliage, fruits and vegetables. Still, certain plants and trees are feeling the effects after our region had a wet spring, followed by hot, dry conditions in July and August.
For one, lilacs have suffered, and certain fruit trees are struggling, too. And now might be the time to consider some things for next season, like which plants and flowers do better in hotter, drier conditions due to human-caused climate change.
Brown lilac leaves
Q: You all are probably already answered this question but what’s up with the lilacs? Why are their leaves turning brown and falling off? - Kelly, in Waitsfield
A: Plenty of rain in spring and early summer set the stage for certain fungal diseases to take hold, and one of those could be affecting your lilac bushes.
The leaves may have turned brown or black in the rainy weather, and then, when the temperatures got hot and conditions turned dry in July and August, those already-compromised leaves likely dried out completely and dropped off.
The course of action to help your lilacs is two-fold: First, clean up the dropped leaves and remove them from the area completely. That way, you'll be getting rid any disease inoculum that could overwinter if left in place.
The next thing to do is stay calm, knowing lilacs are hardy. Check the overall health of yours with this test: If your lilacs still have green buds on them, and if you nick the stem and see green underneath, the lilac is healthy and will bounce back next year.
Tiny red bugs on false sunflower
Q: I have lots and lots of very tall yellow daisy plants and all of their stems are absolutely covered with tiny red bugs and the flowers are mostly dead - what are they and what can be done, other than cutting them all down!? By the way I have these plants all over the place in various settings of full sun, part sun, and all have the same issue this year. I'm not trying to save them at this point in the season but wondering what causes this and will they be back next year? - Ann, in Strafford
A: The tiny red bugs are likely aphids on your false sunflower or heliopsis plants. That's a common problem befalling heliopsis.
If you love them and want to continue to grow them, the cure may seem drastic: Cut them down and remove them.
Clean up the area, too, then next year, start checking the stems in early summer. As soon as you see red aphids, spray with insecticidal soap or neem oil. Continue to spray throughout the season to keep them in check and enjoy the beautiful yellow flowers!
What is attacking our plum tree?
Q: Thank you for your gardening tips over the years!! Hopefully you can help save our plum tree which has been sick for the past few years. Attached are some pictures of the tree and the leaves which might give you a hint as to what the problem is. - Thom, via email
A: Borers could be the culprit here.
Borers are insects like certain beetles or larvae that can tunnel into the stems of fruit trees. When they do, the damage caused can potentially kill the tree.
To know for sure if its borers infesting your plum trees, check the main stem and trunk. If you see tiny holes, that's likely due to borers. Unfortunately, once they start tunneling, there isn't a lot you can do.
If the tree is on the younger side, you could wrap the trunk this winter and into next year. Wrapping the trunk could provide a bit of protection from any new insects coming in.
And next spring, remove grass from around the trunk.
Add some fertilizer and bark mulch or wood chips instead, then keep it well watered and see what happens.
Seeking plants that thrive in hot, dry conditions
Q: I accept to my dismay we are getting warmer. This year (second drought summer in a row by my count), I noticed some plants withstood hot and dry much better: hydrangeas, black-eyed Susans, echinacea. But my pyeweed, bee balms and some others needed help. I will be doing some transplanting this fall. Which perennials are best for all-day Vermont sun and which should I move to areas with less sun? I am open to new plants/flowers on the idea we are getting warmer. - Kathy, in Royalton
A: Human-caused climate change is making stretches of hotter, drier weather, along with periods of heavy rains and flooding events more frequent.
When considering what to plant in our gardens and landscape, we can choose plants, flowers and trees that thrive in those conditions.
Flowering plants like California poppies, sedum, salvia, coneflowers, verbena and lantana thrive in hotter, drier weather, so favor those in the hot spots in your yard.
Plum tuckered out with no fruit
Q: Our plum tree has growths and we would like to know what to do about them. Also our plum and pear trees are five years old. There is very little flowering and no fruit. - Bob and Kathleen, in Enosburg
A: Your plum tree has a fungus known as black knot. It attacks both domestic and wild plum and cherry trees.
The key to combating it is removal; if you leave it there, the spores will spread throughout the tree.
The optimal time to remove it is in late winter.
When you remove it, cut the stem back about 6 inches or so below where the knot is. If that deforms the tree, just remove the whole branch.
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