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Welcome to the "Ask Janet Carson" portion of our website. Here you will find Janet Carson's current "In the Garden" Questions and Answers found weekly in "The Arkansas Democrat/Gazette" Saturday edition. Have fun reading these pages and check back with us weekly. This page is constantly updated and new questions are added on Monday following their appearance in the paper. So stay tuned...

All of the Questions & Answers that Janet writes for all publications are archived.

In the Garden with Janet B. Carson

 

May 12, 2018

Question

I have a batch of Iris that for years have had no plant blooms or perhaps one or two.  Last fall I took them all up and mixed in additional soil to a re-planted bed of twenty bulbs.  In February I lightly fertilized the bed. This week I finally have one of the twenty Iris plants with three beautiful white blooms.  All the other plants have multiple, healthy leaves on them but no blooms.  Nothing has changed.  Why is this thus?

Answer

We usually see non-blooming iris if they are grown in the shade, or they are too crowded.  Iris will not bloom if they are not getting enough sunlight—they need a minimum of 6-8 hours per day, and more would be better.  If they get too crowded, they won’t bloom, but I assume you divided them when you replanted them.  Iris plants should be divided in late July to early August.  There should be two to three fans per division. A fan is what the fan shaped arrangement of leaves coming out of the iris rhizome is called.  If you divide them too severely, to only one fan per division, they often will not bloom for the next year until they build up more energy.   You also need to make sure you have not planted the iris rhizome too deeply.  Ideally you want the rhizome to be half exposed.  . 


Question

When do I need to quit picking my asparagus? I have been harvesting heavily for 2 months. I know it needs a break but it is so good.  

  
AnswerThere is nothing better than fresh asparagus. Quit harvesting when the spears are smaller than a pencil in diameter.  If you over-harvest, it can wear the plants out and it will produce poorly in future years. 


Question

Do you know of any way other than continually snipping, to get rid of crepe myrtle suckers?   I tried just letting some of them grow to branches, but that will take forever and looked so bad I finally cut them.  Do you think I could Put Round Up on some of the suckers without killing the entire plant?


 

 Answer

Some varieties of crape myrtles will sucker every year for their entire lives, while others don’t produce any suckers. If you have a suckering variety, cutting out the suckers right beneath the soil surface once or twice a season should suffice.  I would not recommend using Roundup as the suckers are attached to the mother plant and you could cause damage. 

 


Question

Hi Janet, love your article in the ADG (and your radio show in the old days).  Can you tell me what summer annual blooms a lot and can take full afternoon sun?  These will be replacing my violas, which are glorious.  Whatever it is probably needs to be a foot or less tall.

Answer

Thanks!  The violas did bounce back nicely this spring and have been stunning in many gardens. For plants that are no more than 12 inches tall and can take full sun, consider replacing with vinca (periwinkle), lantana (look at mature sizes, because some get much taller, while others stay compact), and Zahara or Profusion zinnias in a wide range of colors—the double orange is stunning!

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Question

I have 9 Euonymus shrubs across the front of my house (east side).  Last year one of them got infected and died before I noticed the problem. I then noticed some of the others were also beginning to look bad. I took some of the infected branches to the nursery and they told me that it was euonymus scale and sold me 55% Malathion for treatment. I sprayed them twice (in the fall) and they looked better. Then in February I noticed 3 of them had become infected again and some branches were already dead. I sprayed them again with the Malathion and removed the dead branches. They are now greening up and putting on new growth, but I think I can see the scale coming back. I started to spray again, but noticed the instructions on the Malathion says “do not apply more than 2 times a year". Is it safe for me to use more often? If not what can I do to kill this scale?

Answer

 

If you grow the golden euonymus plants, expect to see euonymus scale every year.  That is the limitation to growing this plant.  Euonymus scale will not kill a plant overnight, but over time they will limit their growth and overall vigor, which can lead to an early death.  The way to identify the scale is to look at the backs of the leaves, the stems and in bad cases, even on the upper surface of the leaf.  It looks like someone has sprinkled them with salt and pepper.  Scale insects are difficult to kill with a contact spray—which Malathion is, since the insects cover the undersurface of the leaves, the stems and more, which makes thorough coverage difficult.  If the insecticide doesn’t come in contact with the insect, it can’t kill it.  You may have knocked back some of the crawlers, but not many of the adults.  For scale insects it is better to use a systemic insecticide which can kill the insects as they feed from the inside.   Orthene is one, Imidicloprid (Merit, Fertilome Tree & Shrub Systemic Insect Drench, or Bayer Advanced Tree & Shrub insecticide) will do a great job. 


 

 

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