Garden columnist Dan Gill answers readers questions each week. To send a question, email Gill at [email protected].
My live oak trees have been dropping tons of greenish brown things over the past week or so. Can I leave this stuff where it is on my lawn? Can I leave it where there is no grass? If I have to pick it up, what should I do with it? — Fred Piazzolla
The things falling from the live oaks recently are male catkins. Their structures carry the male flowers of the trees.
Live oaks, like many shade trees, produce separate male and female flowers on the same plant. Live oaks have female flowers that will eventually turn into acorns. But the male flowers must spread pollen to the female flowers for that to happen.
To do this, the male flowers release a lot of pollen into the air. The pollen will then drift to the female flowers on the wind.
This is how most of our shade trees and weedy grasses are blooming right now, which is why there is so much pollen in the air.
As to your questions about what to do with the fallen catkins, here’s what I recommend. In areas where there is no grass, leave them. If the layer of catkins is less than an inch thick, try mowing. If it mostly disappears with mowing, there is no need to remove it.
If the ground is more than an inch thick and the grass is completely buried, rake up as much as you can and use it as mulch in your beds or add it to your compost pile.
You can do the same thing with catkins you sweep up from drives, patios and walkways. Don’t just throw this stuff away in the trash — put it to good use.
How should I dig up and store tulip bulbs in Louisiana? When should I plant them again? — Karen
Tulips do not rebloom well in our climate. After all your work, you might get a few small flowers at most. Most of the bulbs won’t bloom at all.
I recommend simply pulling them up, chopping them and putting them in your compost. In spite of this, most gardeners like to test things on their own. If you still want to do that, here’s what you need to do:
Wait until the foliage is mostly yellow. Dig the bulbs and remove the foliage. Do not water the bulbs for a few days. After that, keep them inside in paper bags during the summer.
In early November, refrigerate the bulbs in the vegetable bin of your refrigerator. Plant the bulbs at the end of December or early January.
We have a camellia bush that has a lot of white, slightly fuzzy material under the leaves. The tops of the leaves are mottled with yellow. The buds show up and look like they’re growing, but most of them don’t open. Only a few of them do, and they make a flower. What can we do and when should we do it to get better blooms next year now that the season is over? — George Zeitouni
Your plants have an insect called tea scale on them, which could be why they aren’t blooming as much as they should. Put a spray of Bayer Advanced Tree and Shrub Insect Control or another product with imidacloprid on the camellia and follow the directions on the label.
You can also get better control by spraying the camellia with horticultural oil a few times, as directed on the label. Brands like Year Round Spray Oil, All Seasons Spray Oil, Volck Oil, and others are available. Spray thoroughly under the leaves.
The tea scale insects will not disappear right away, but don’t assume the treatment has not worked. Watch the new growth as it appears in the spring and matures in early summer. If it stays clean and scale free, your treatments have been effective.
SAVE EASTER LILIES: Don’t throw away potted Easter lilies after Easter. You can plant your Easter lily outside in a garden bed after the flowers have died back. It will bloom there for years to come. Cut off the plant’s dead flowers, take it out of the pot, and plant it in a bed that has been prepared well and filled with compost. Choose a location that receives sun through most of the day with some shade in the afternoon. Plant so that the top of the root ball is even or slightly below the soil surface. Easter lilies go dormant in midsummer. In the middle of summer, when the leaves turn yellow, cut the plant back to the ground and mark the spot so you can find it again. Easter lilies will begin to grow again in fall, around October. Fertilize them at that time.
DEAD HEAD: While you can, keep removing faded or dead flowers from cool-season bedding plants like dianthus, foxglove, columbine, and snapdragon. This is called deadheading. Not only does this keep the plants looking neat, but it also tends to promote extended flowering.
SUMMER BULBS: Plant bulbs that bloom in the summer, like crocosmia, gingers, canna, pineapple lily (Eucomis), elephant ears, crinum, agapanthus, and more.
There are stakes in tomato plants to keep them from spreading out on the ground, where the fruit would be more likely to go bad. Once the first flower cluster shows up, move the stake to the other side of the plant’s stem. There will be one stem from which all the flower clusters grow. This way, the fruit won’t get stuck between the stake and the stem as it grows.
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Dan Gill is a retired consumer horticulture specialist with the LSU AgCenter. He hosts the “Garden Show” on WWL-AM Saturdays at 9 a. m. Email gardening questions to gnogardening@agcenter. lsu. edu.
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Oak trees are iconic landscape trees treasured for their beauty, shade, and overall majesty. While oaks provide interest year-round, spring is an especially captivating time as they awaken from winter dormancy. In this article, we’ll look at the signs of spring in oak trees reasons to avoid pruning in spring, and how to care for oaks as warmer weather arrives.
Awakening: An Oak Tree in Spring
After a long winter, it’s exciting to observe the first signs of life in oak trees as spring gets underway. Here are some of the changes you can witness
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Buds swell and open – Around March/April, fat leaf and flower buds that formed last summer begin expanding and unfurling. It’s a welcome signal of warmer weather ahead.
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New leaves emerge – The buds give rise to fresh, bright green new leaves and catkins. Oak leaves start out crumpled and delicate before expanding to maturity
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Flowers bloom – Some oaks like pin oaks and post oaks produce dangling catkins that release pollen for wind fertilization.
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Birds and critters return – Birds flock back to oak trees for food sources like buds, flowers, insects, and seeds. Squirrels resume their antics.
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Moss and lichens thrive – These epiphytes resume active growth on oak bark and branches in spring’s warmer, moist conditions.
Observing an oak tree as it springs back to life after a dormant winter is endlessly fascinating. Make sure to watch closely for all the magic of spring!
Why Pruning Oaks in Spring is a Bad Idea
It’s generally best not to prune oak trees between late winter through early summer. Here’s why:
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Oak wilt risk – Fresh pruning wounds attract beetles that can spread fungus spores causing the deadly oak wilt disease. Avoid pruning from February-July when transmission risk peaks.
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Sap bleeding – Cutting branches causes heavy sap bleeding from wounds. This can attract insects that spread disease.
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Added stress – Pruning robs trees of energy right when they need it most to produce leaves and acorns.
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Reduced photosynthesis – Cutting branches and leaves limits food production from photosynthesis when it needs to be high.
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Weakened structure – Improper pruning in spring leaves trees poorly structured to withstand summer wind and storms.
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Eye-catching wounds – Unseemly pruning wounds stand out clearly against bare branches before leaf-out.
Of course, there are exceptions where pruning to remove damaged branches after a storm overrides other risks. But in general, restraint is advised.
Signs Your Oak Tree Needs Corrective Pruning
While pruning oaks in spring is inadvisable, certain warning signs mean you shouldn’t delay pruning needs until later:
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Broken, cracked, or dead branches – These should be pruned immediately to prevent injuries or further harm.
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Cavities or cankers – Prune away diseased or pest-infested branches so problems don’t worsen.
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Hazards over homes or structures – Branches threatening roofs or power lines require urgent removal before damage.
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Dense, crowded branching – Poor structure from excessive inward or overlaying branches may necessitate judicious pruning.
Take pictures beforehand documenting the issues. Only prune the bare minimum to resolve immediate dangers or defects.
Caring for Oak Trees in Springtime
Beyond holding off on pruning, here are some tips for tending to your oaks in spring:
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Water – Ensure young or transplanted trees receive ample water as growth accelerates. Even mature trees appreciate a deep watering.
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Mulch – Apply 2-4 inches of wood chip mulch around the root zone to retain moisture and suppress weeds. Keep mulch a few inches from the trunk.
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Fertilize – Apply a balanced granular tree fertilizer to promote lush spring growth. Follow label directions.
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Check for pests – Monitor for early signs of pest infestations like galls or leaf notching and address issues promptly.
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Remove deadwood – Carefully remove any small dead branches by hand without tools to tidy up trees.
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Monitor diseases – Watch for evidence of anthracnose or bacterial leaf scorch and have an arborist inspect affected trees.
With appropriate care tailored to seasonal needs, your prized oak trees will coast through spring ready for vigorous summer growth ahead.
Signs of Healthy Oak Tree Growth in Spring
When oaks are happy and growing well, you can look for these positive signs:
- Dark green leaves unfurling from plump buds
- Profuse light green clusters of new leaves at branch tips
- Expanding leaf size as spring progresses
- Delicate chains of flowers blooming from buds
- Active leaf and twig growth increasing in speed
- Bright active moss and lichen on bark and branches
- New leaves rapidly filling out bare branches
Fast spring growth allows oaks to maximize light interception and food production when conditions are ideal. It directly influences their overall vigor.
What to Expect Next as Spring Winds Down
In late spring, oak trees transition to the next phase of growth:
- Catkins and flowers give way to developing acorns and seeds
- Leaves reach full size and darken from light green to deeper green
- Shoot elongation and leaf expansion slows as trees focus on storage for summer
- Shedding of older leaves to make way for new ones
- Bark darkening from light gray back to rugged darker tones
Soon the oak’s yearly growth cycle will ramp up into high gear in summer’s long days and peak sunlight hours. But for now, marvel at spring’s magic as your oak awakens this new growing season full of possibilities. With a little help from you, it will grow into a towering testament to nature’s glory.
The Curse of the Live Oak Tree!
When do oak trees bloom?
Mature oak trees bloom during the spring, just before putting out leaves. Only trees that produce acorns flower; if an oak tree is younger than 20 or older than 80 years old, it may not produce flowers or acorns. Oak trees may bloom late during periods of cold weather, or they may bloom early if the weather warms up sooner than normal.
When do oak trees put out their leaves?
Oak trees begin to put out their leaves during the spring, again between March and May depending on location, species, and environmental factors. Leaves begin budding around the same time as the flowers are out and usually begin to open as the flowers are dying.
Why are there so many oak flowers this spring?
The large amount of oak flowers this spring indicates a big acorn crop this fall. Trees are so cool, and they often surprise us. This year, for example, the red oaks, live oaks, bur oaks, Mexican white oaks, Lacey oaks, and most other oaks have given us huge flower production. Why?
Why do oak trees bloom late?
Oak trees may bloom late during periods of cold weather, or they may bloom early if the weather warms up sooner than normal. Oak blossoms may be harmed by late season frost, which in turn can affect acorn production later on in the year.