May 7, 1999

Planting Dahlias

Contrary to some claims that the dahlia is one of the easiest flowers to grow, there are several cultural practices that need to be carefully followed to grow them successfully.

Dahlias can be planted outdoors after the last frost in your area. In central Iowa, dahlias can be planted around May 10 to 15. Gardeners in southern Iowa can plant a few days earlier. Wait several additional days in northern areas. A frost or freeze can damage or destroy the plants.

Bacterial Blight on Lilac

Are you wondering why some lilacs have sick-looking leaves and twigs at this time of the year? In early spring when the weather is cool and wet, the bacterium Pseudomonas syringae may attack newly emerging shoots, flower buds, and leaves.

It causes water-soaked brown spots on leaves and twigs. Eventually, infected plant parts turn completely black, then wither and die.

Mushroom Hunting

The warming weather of April and May causes some people to venture outdoors on mushroom seeking missions. Morel hunting is especially popular at this time of year. The short morel season usually lasts about 4-5 weeks. Questions often arise about the identity and edibility of mushrooms that are found. Pm-1204 Morels, false morels, and other cup fungi is an excellent reference that includes color photos of many of the common mushrooms that are found at this time of year. NCR 129 Mushrooms and other related fungi is another useful reference.