Ask the ISU Experts

How do I destroy volunteer mulberry trees in my hedge? 

Cutting off volunteer trees near ground level will not destroy most trees. Most trees that are cut off near ground level will produce new shoots at their base.  To effectively kill unwanted trees, their root systems must be removed or destroyed. 

One way to destroy small volunteer mulberry trees is to dig them up. The root systems of small trees are not very large. Digging up the small trees is a viable option. 

The application of a systemic, non-selective herbicide, such as glyphosate (Roundup), is another way to destroy volunteer trees. Glyphosate is most effective when applied to actively growing plants. Therefore, wait until the trees are fully leafed out and actively growing. Anytime from late May to early September should be fine. At this time, cut off the trees near the ground and immediately apply glyphosate to the cut surfaces. A small, foam-type paintbrush makes a good applicator. The exposed, live tissue at the cut surfaces will absorb the herbicide and translocate it down into the roots, effectively destroying the trees.  

I would like to start some geraniums from seeds.  When should I sow the seeds indoors? 

Geraniums are relatively easy to grow from seeds. However, they are slow growing. Geranium seeds should be sown in early to mid-February to produce flowering plants for spring. Flowering occurs approximately 13 to 15 weeks after sowing. 

When can I transplant my rhubarb? 

Early spring is an excellent time to transplant rhubarb. As soon as the ground is workable, carefully dig up the plants in early spring before growth begins. Dig deeply to insure getting a large portion of each plant’s root system.  Large rhubarb plants can also be divided.  Divide large clumps with a sharp spade or butcher knife. Each section (division) should have at least one or two buds and a portion of the root system. 

Replant the rhubarb as soon as possible. The roots must not be allowed to dry out prior to planting. If the rhubarb can’t be planted immediately, place the clumps in a plastic bag and store them in a cool, dark location. This temporary storage should be fine for a few days. 

Rhubarb is easy to grow. It performs best in full sun. Avoid shady sites near large trees or shrubs. Rhubarb also requires fertile, well-drained soils that are high in organic matter.Sandy and clay soils can be improved by incorporating large quantities of compost, barnyard manure or other forms of organic matter into the soil before planting. 

When planting rhubarb, place each section upright in the planting hole with the buds 1 to 2 inches below the soil surface. Space the plants about 3 feet apart. After planting, water thoroughly. Continue to water the plants throughout the first growing season. During dry weather, a deep soaking every 7 to 10 days should be adequate. 

To aid establishment, don’t harvest any rhubarb the first two years after planting.  Rhubarb can be harvested for four to six weeks in the third year and until mid-June in succeeding years. 

Rhubarb can also be transplanted in early fall (mid-September to early October). Mulch fall planted rhubarb with several inches of straw in mid-November.