Ask a Master Gardener: General gardening questions

When is the best time of the day to transplant vegetables?

Afternoon to evening, because the transplant will be exposed to less heat and stress.

May I use treated wood to make my raised bed?

Do not use railroad ties because creosote vapors can be toxic to plants. Treated lumber should not be in direct contact with a root vegetable like potatoes or beets. You could line your bed with a landscape fabric for protection.

Should I plant the vegetable seeds I had left over from planting last season's garden?

In general, if the seeds have been stored well, many of them will germinate fairly well the second year. Expect reduced germination, however, so plant thicker than suggested. If good germination results, thin seedlings appropriately. Many garden seeds may be kept for 2 years or even longer in a cool, dry location. Place in a tight jar or can keep them dry. Seeds that lose vigor most rapidly in storage include sweet corn, lettuce, okra, onion, parsley, parsnip and salsify.

What is the best kind of manure for the garden?

Cattle, horse, or swine manures containing straw are the best. Cattle and pig manure contains 5 to 10 pounds of nitrogen per ton. Poultry and sheep manure have higher levels of nitrogen and may supply more nitrogen than needed early in the season. Whatever manure is used, don't apply fresh manure to the garden before planting. It is preferable to compost the manure for about a year before using. It may also be plowed under in late summer for planting a garden the following spring.

Is it possible to apply too much lime to the garden?

Yes. Most vegetables grow best in soils slightly acid. Excess liming can make the soil too alkaline, which reduces the availability of some nutrients and reduces plant growth.

Are wood ashes harmful to the garden?

No. Wood ashes supply potassium as well as some other nutrients to the soil. They also make the soil more alkaline. Have your garden soil tested every 5 years to determine pH. Don't use wood ashes when pH readings are above 7.0.

How much cattle or barnyard manure can be used on the garden?

It is generally safe to use composted manures at a rate of 50 to 100 pounds per 100 square feet of garden.

Is it safe to add sawdust (shavings, other wood products) to the garden?

Yes. However, it is better to have these products composted for a year before addition. Wood products, especially when fresh, tie up nitrogen so plants may become starved. When wood products are added, additional nitrogen is necessary. A nitrogen fertilizer such as ammonium nitrate (34-0-0) may be added at about 3/4 cup per bushel of sawdust, or 27 pounds per 1,000 square feet of area with a layer of sawdust 1 inch deep. Sawdust is excellent for improving the structure of the soil.

(Source: Dr. David Trinklein, MU Extension; Original author: R.R. Rothenberger)

Dhruba Dhakal, PhD is a University of Missouri Extension Horticulturist, serving to Missourians about a decade in Central Missouri. Dhruba can be contacted at [email protected] with gardening questions.