Walter Reeves: A pretty tree you don’t want in your landscape

The clusters of flowers are beautiful, but the paulownia tree (princess tree) soon becomes a thug in the landscape. (Walter Reeves for The Atlanta Journal-Constitution)

Credit: Walter Reeves

Credit: Walter Reeves

The clusters of flowers are beautiful, but the paulownia tree (princess tree) soon becomes a thug in the landscape. (Walter Reeves for The Atlanta Journal-Constitution)

Q: What is the name of the tree that we saw on the side of I-75 driving down from Kentucky? It is a large flowering tree with upright clusters of lavender blooms that look a lot like wisteria. It is a vertical cluster that is rocket shaped. The tree appears to be 50 or 60 feet tall. Chuck Matthews, email

A: As soon as you said lavender blooms that look like wisteria on a tree, I knew what it was. The flowers are ornamental, but you don’t want it in your landscape or anywhere else. It is a paulownia or princess tree (Paulownia tomentosa). The individual foxglove-like flowers will soon drop off and over the summer will yield pods of black seeds. Each pod contains up to 2,000 seeds, and a large tree may produce as many as 20 million seeds a year. Young trees can be recognized by the huge size of the leaves and their fast growth rate. I am told the wood is useful for woodworking, and that the tree can be grown commercially for biomass energy, but I recommend its removal whenever seen. See more details at bit.ly/GApaulownia.

Q: When should I mow my Meyer zoysia grass that currently has seed? Should I wait for the seed to fall off, or can I mow now and the seed will germinate? Steve Allen, email

A: The seed heads of Meyer zoysia are distinctive dark purple spikes, but this grass does not produce viable seed. Like most varieties of zoysia, it is established by sod. I have good news: You can mow any time you want to.

Q: I saw a recipe using 30% concentrated vinegar, Dawn and salt to kill weeds. Can I use the same amount of regular vinegar as concentrated vinegar? Can I use table salt instead of Epsom salt? Cathy Sparks, Glennville

A: I truly believe that the manufacturers of Dawn dish detergent are behind this false recipe, which is commonly spread on the internet. Why is it always Dawn, I wonder, when there’s no brand name of any other ingredient? Regular vinegar is not the same as concentrated vinegar. The first one is safe to use in any kitchen. The second one is so dangerous you need to wear gloves and eye protection when using it. And to answer your second question, Epsom salt (magnesium sulfate) is not the same as table salt (sodium chloride). Of the two, table salt would do more damage to weeds than Epsom salt. In closing, use products that are labeled for use as weed control, not kitchen ingredients.

Email Walter at georgiagardener@yahoo.com. Listen to his occasional garden comments on “Green and Growing with Ashley Frasca” Saturday mornings on 95.5 WSB. Visit his website, walterreeves.com, or join his Facebook page at bit.ly/georgiagardener for his latest tips.