Knockout Roses. Photo: Dr. Allen Owings, LSU AgCenter (ret.)

Knockout Roses

Cynthia had questions about the drought and cutting back double knockout rose bushes. Her roses suffered because of the drought but had survived because of watering.

AHA referred to an article by Dan Gill, retired AgCenter horticulturist, who advised, “The first pruning is done anytime from late January to mid-February. Pruning any later will delay the outstanding spring and summer flowering.” Then he also discussed a second pruning, “Another opportunity to cut the bushes back arrives now in late August to early September. Again, you do not have to be too fussy about this. This pruning is not as severe as the late-winter pruning. Plants are generally cut back by about one-third their height depending on how much control is needed. Do not forget to remove any dead canes when you cut the bushes back. Fertilize the bushes immediately after this pruning.”

A bag of live oak acorns. Photo: Brenda Laurence, Beauregard Master Gardener.

Live Oak Acorns

Brenda, a Master Gardener, send an image of acorns and a question, “What is the best way to start oak tree from acorns??”AHA found a website by the “Friends of Live Oaks,” a group of volunteers dedicated to the protection and planting of live oaks. Their website provided list of steps to germinate live oak acorns:

1) Gather off the ground: [You]can pick off trees if turning brown and they easily pop out.

2) Float test: Put acorns in a bucket or bowl of water. Sinkers [are] good. Floaters [are] bad.

3) Heat-treat to kill weevil larva: Put acorns in a warm bath of water 115F-118F degrees not to exceed 120F or you kill the plant. Weevils will float out and die after about 10-15 mins.

4) Plant acorns in ground or pots. No deeper than 2 times the thickness of the acorn. In pots you can protect [acorns] from critters trying to eat them might be best choice.

5) Protect from squirrels.

6) Nurture them & watch them grow!

Supertunia Vista Bubblegum Photo: Dr. Allen Owings, LSU AgCenter (ret.)

Cool Season Flowers

Kyle asked for advice on behalf of a relative, “I am trying to find some plants/ flowers that will stay pretty through winter. My mother-in-law has dementia. She loves to sit and look out the window at the pretty flowers. I try to keep them looking good for her. I am new to the flower world, and I love it now, but not sure what to plant and when. “

AHA looked up the Louisiana Super Plant list for cool season flowers and shared information about these seasonal flowers with Kyle.

• Supertunia Vista Bubblegum
• Homestead Purple Verbena
• Diamonds Blue Delphinium
• Redbor Kale
• Swan Columbine
• Amazon Dianthus

Louisiana Super Plants have a proven record of accomplishment having gone through several years of university evaluations and observations. Louisiana Super Plants are “university tested, and industry approved.” The Super Plants listed above, in general, can be planted from October to March.

A blackberry plant with a couple of issues. Photo: Melissa Adams

Ailing Blackberry Plant

Melissa shared some images and sent this message, “I have a new blackberry patch starting at my house. They are the Ponca variety. Would you look at these photos and diagnose my problem. Not sure if it is serious or not but want to be proactive. “ Melissa has a couple of issues with her blackberry plant based on the image she sent. The dark purple coloring in the purple circle indicates that her plant has a phosphorus deficiency. A soil test will provide results and fertilizer recommendations to adjust this nutrient deficiency. AgCenter offices provide soil sampling kits for soil testing.

The leafspots in the red circle look like a fungal infection. Fungicides with copper or captan can prevent future infection but will not cure the current infections.