Ask the Master Gardener: Are compost or wood chips better for your garden?

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The Springfield News-Leader in Springfield, Missouri, partners with the Master Gardeners of Green County each week to bring readers a question-and-answer column with some of the expert horticulturists in the region.

Colleges and universities in the U.S. typically offer Master Gardener programs, which provide "intensive horticultural training," according to the American Horticultural Society. The certified Master Gardeners then volunteer as lecturers, researchers and gardeners in their communities. For more information about Master Gardener programs in your community, the American Horticultural Society created this page with local resources.

Here's a sample of some of the recent questions amateur gardeners had for the masters of the craft.

When should I prune my hydrangea? I've gotten conflicting answers, so am a bit confused on what to do.

This can be confusing, because there are many different types of hydrangeas! The answer depends on what type you have and when it blooms. In general, they should be pruned after blooming. Hydrangeas that bloom in spring to early summer should be pruned one to two months after bloom, since these varieties bloom on old wood. Pruning too late after bloom could result in fewer blooms the next year, since the potential flower buds will have been removed. Fall-blooming varieties should be pruned in late winter/early spring, before buds form, as they bloom on new growth.

Tips to successful pruning include cutting up to one-third of the stems, especially old ones, but also any new ones that appear weak, cutting to the ground and removing those stems. Common mistakes in pruning that may lead to fewer flowers include pruning at the wrong time, cutting off flower buds, and cutting off too much of the shrub.

It is okay to add wood chips to my garden instead of compost in order to add more nutrients to the soil?

I would not recommend adding fresh wood chips directly to your garden soil. Compost is useful in revitalizing your garden because it contains readily available nutrients, providing benefits to plants immediately. Wood chips take much longer to break down, thus are not a quick source of nutrients. Wood chips are best used for mulch to keep weeds down and then added to the garden soil after they have broken down into more useful nutrients. Wood chips can also be composted 50/50 with "green" materials, such as grass clippings or manure, to balance out the ratio of carbon to nitrogen. After "cooking" for a while, the resulting compost can be added to the garden soil.

When is a good time to divide and transplant my "Live Forever"? What about some of the other types of sedum or other succulents in my garden?

"Live Forever" is a plant of many names! This name is sometimes applied to other plants in the sedum family, but I am assuming you are asking about stonecrop sedum. Older garden books refer to this plant as Sedum telephium, however the correct botanical name is now Hylotelephium telephium. There are different varieties, including "Autumn Joy" and "Brilliant." The plant can be moved in fall or in spring, as long as the soil is cooler and wet. If moving in the spring, wait until new growth is showing. This can be done every three to four years. In truth, these plants are very sturdy and can be transplanted whenever the soil is workable, just make sure to water the soil well the day before digging.

As for other types of succulents, spring blooming types can be moved in the fall, at least eight weeks before a hard freeze. Hen and chicks should be moved in spring or early summer, after the last frost has occurred.

Readers can pose questions or get more information by calling 417-874-2963 and talking to one of the trained volunteers staffing the Mas­ter Gardener Hotline at the University of Missouri Exten­sion Center in Greene County located inside the Botanical Center, 2400 S. Scenic Ave., Springfield, MO 65807.