Hollow pampas grass clump is difficult to fix

Pampas grass clumps die in the center because the roots prefer to grow outward, instead of inward, where old roots and compacted soil deter growth. (Walter Reeves for The Atlanta Journal-Constitution)
Pampas grass clumps die in the center because the roots prefer to grow outward, instead of inward, where old roots and compacted soil deter growth. (Walter Reeves for The Atlanta Journal-Constitution)

Credit: Walter Reeves

Credit: Walter Reeves

Q: I have some pampas grass which is dead in the center. Does cleaning it out promote additional growth there? Steve Stern, email

A: This is a common problem with pampas grass. It is almost unavoidable, but proper pruning can help you deter it. You should cut a clump of pampas grass back to 12 inches tall in January or February. DO NOT burn it. Use a gloved hand to rake out all of the dead material in the center of the clump. Failure to cut it low enough and to get all of the dead material out of the center is what causes a clump of grass to die in the middle. If your pampas grass already has this problem, it’s almost impossible to get it to sprout in the center. Your best course of action is to dig up the whole clump, divide it into quarters and replant one quarter in the spot. Use the remaining three grass clumps in other places or give them away. In my experience, digging pampas grass is backbreaking labor. A heavy mattock is my preferred tool.

Q: We want to plant 10 American Pillar arborvitae in our yard. Would I have any issues if the ground is frozen when we plant? Ray in Bartow County

A: Pam Knox, director of the UGA Weather Network, looked at the number of days on which the 2-inch soil temperature at the Rome weather station (closest to Bartow County) was at or below freezing. She found only two days in the last 10 years on which the soil was frozen. Farther north, in Blairsville or Ringgold, the soil might be colder, but my bet is that even then there are many days of winter when the soil in North Georgia is not frozen. It is fine to plant the arborvitae now. But it is critical to keep the root system moist for at least six months lest the roots dry out.

Q: Online guides say that you can cut main limbs of a lilac to the ground to encourage new growth. My single-trunk lilac is 10 feet tall but I want it to be lower and bushy. Beryle Tylar, email

A: I would wait until late February, just when the weather is getting a little warmer, and make a pruning cut 2 or 3 feet from the ground. That’s the time you’re most likely to get re-sprouting from dormant buds. After sprouts emerge in spring, clip off the growing tip of each one when it is 12 inches long. That should result in a more attractive and bushy plant.

Walter’s email address is georgiagardener@yahoo.com. Listen to his comments at 6:35 a.m. on “Green and Growing with Ashley Frasca” Saturday mornings on 95.5 WSB. Visit his website, www.walterreeves.com, follow him on Twitter @walterreeves, on Pinterest, or join his Facebook Page at bit.ly/georgiagardener.

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