The Journal Gazette
Saturday, May 23, 2020 1:00 am

Spring is time for questions, answers

Ricky Kemery

Thanks to readers who are sending in questions and kind comments this spring. Here are a few.

I have read that I must replace the soil in my garden containers located by the entrance of my house yearly. Is this true? I grow petunias in the containers every year.

The “experts” say to replace your soil each year and sterilize the containers, because insects and disease organisms can build up in the soil. This can happen especially if you grow the same species every year.

My feeling – because the soil-less mix can wear out over time – is to replace it yearly to a depth of 6 to 8 inches with fresh mix. Just put the mix you take out in a landscape bed or your veggie garden. It will not harm the plants growing there. I would replace all the soil in your container only if you have increased insect or diseases over time. When you replace the soil, clean the container if possible with an eco-friendly disinfectant.

It will help if you change the annual species you plant every two to three years. This is the same concept as crop rotation in a garden and or field.

The roots of our soft maple tree in the front yard are sticking out so far above the ground that it is exceedingly difficult to mow. Can we just remove the roots completely or grind them down so we can mow?

Silver maple trees often have brace roots that appear above ground level. This phenomenon is more prevalent on clay compacted soils that are common on urban sites in our area. Brace roots anchor and stabilize the trees, unlike the network of feeder roots (found mostly in the upper 24 inches of soil) that take in water and nutrients. The brace roots of the silver maple are also responsible for buckling sidewalks and driveways.

It will not hurt to cover the offending roots with soil or mulch because in reality silver maples are almost impossible to kill. It is just one reason I would never recommend planting this tree on an urban site. Over time, this naughty tree will once again send up the brace roots above grade, so this is not a one-and-done deal.

Don't remove or grind those roots because doing so will make the tree more prone to blowing over in a severe storm.

Sometimes oaks or other species also have roots that appear above ground level. I do not recommend covering those roots.

My daffodils did not have flowers this spring. I have read that over-crowding can cause this. Can I divide and move them now, or should I wait until the foliage dies back?

I prefer to wait until fall to move because by the time the foliage dies back it will be early summer. The survival rate of spring flowering bulbs transplanted in late spring or summer is low. Mark the area or plants with small stakes and move in the fall. Your bulbs will thank you.

The Plant Medic, written by Ricky Kemery, appears every other Saturday. Kemery retired as the extension educator for horticulture at the Allen County Purdue Extension Service. To send him a question, email

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