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Woodchips should be used as mulch not amendment

I think there is an epidemic of people adding wood chips to the soil as an amendment. Wood chips applied to the soil surface as a mulch is OK, but mixing these into the soil can lead to problems if you aren’t careful.

Part of this trend is fueled by social media like YouTube and internet discussion groups and experimentation by gardeners with concepts such as Hugelkulture. It works, but it must be done correctly.

Adding wood debris to the soil for its improvement requires a balance between the carbon load added to the soil in the form of wood chips, water and nitrogen added to the soil at the same time to help it rot. These sources of nitrogen help wood chips to decompose and rot without affecting other plants growing in the same area.

Without this additional nitrogen, plants growing in the area yellow and might die. Seeds planted in these types of amended soils fail to germinate.

Additional nitrogen can be added by chopping up kitchen scraps, green waste from the yard such as leaves and grass clippings and mixing in commercial fertilizers high in nitrogen such as 21-0-0. Rotting is sped up by turning it and keeping it moist.

Q: I planted two rows of corn, separated by some peas, but one row closest to the fence never came up. I replanted that row, and now one row of corn is really struggling while the other, closest to the peas, is doing well.

A: Amend the garden soil with compost to improve drainage. Poor drainage can cause a lack of germination.

Lightly dust the seed with Captan fungicide to improve seed germination when planted in cold or wet soils. Tear a corner of the seed packet and place a small amount of fungicide inside and shake it. Always wear gloves when planting seed treated with a fungicide.

I strongly encourage you to not plant the same type of crops in the same area as previous years. Instead, plant in new locations in the garden bed and rotate them back to this spot only after three to five years. That technique helps keep plant diseases minimized.

Mixing wood chips into the soil before planting can also cause poor seed germination. Corn needs lots of nitrogen fertilizer when it’s growing. The rotting of wood chips in the soil also requires a lot of nitrogen fertilizer, so make sure enough nitrogen fertilizer has been added to the soil to fuel both growing corn and rotting wood chips.

Peas are a winter crop while corn is a summer crop, and they should not be planted at the same time in the spring unless you are prepared for a short harvest of peas. Also, sweet corn needs more than two rows planted for its kernels to fill out the ears properly because it is wind pollinated.

Plant at least four rows of corn rather than only two. Plant corn in small blocks rather than rows if the area your planting is small so the ears fill out better.

Both corn and peas have large seeds so try presoaking large seeds, sometimes called pre-germinating, before planting to get faster germination. They should soak long enough for the seeds to swell with water. Soak large seeds in tepid water for several hours before planting. That allows the seed to start the germination process without planting.

It’s important to plant the seeds at the right time of year: peas in the fall through winter months for a winter crop and corn in mid-spring or late summer for an early summer or fall crop.

When pre-germinating seeds, mix a small amount of your favorite water-soluble fertilizer into the fresh water, with a tiny amount of liquid soap. That speeds up germination. When the seed absorbs water at the very beginning, called imbibition, the fertilizer will be taken inside the seed with the water, and early growth is more rapid.

Q: We bought a property in Redding, California, and it has a pretty sad-looking peach tree on the property. Many of the limbs are dead, and the live ones are dripping sap. Do we need to get rid of this tree? Is there any way to prevent this from happening again?

A: Peach trees are magnets for wood-boring insects, aka borers, in our climate. That is the main reason most peach trees are not as long-lived as other fruit trees. This insect never enters the soil, so the soil is usually not a problem. Only the tree. If the damage to the tree is severe, remove and replace it.

Once trees are attacked by these types of borers, they frequently enter a death spiral, and there is not much you can do without using insecticides. Even applying an insecticide is not a guarantee the tree will be cured. Applying a systemic insecticide containing Imidacloprid as a soil drench soon after flowering might kill borers still inside the tree and give the tree some protection for a few months.

Limbs dying because of this insect are normally seen during the summer, but the damage they cause inside the tree starts in the spring. These insects are attracted to trees damaged by intense sunlight, but sometimes they infest trees that appear not to be damaged at all.

As an added protection, make sure the tree is pruned, watered and fertilized so that it has a full canopy that protects its limbs and trunk from intense sunlight. It also helps to shade the trunk or paint it with diluted white latex paint.

Make sure the tree is getting enough water by irrigating it with at least four drip emitters spaced under the canopy. With newly planted trees, these emitters should be about 12 inches from the trunk in a square pattern and more emitters added as the tree gets larger.

Q: Last week I pulled the vines growing up the sides of my house to paint the exterior. These vines included Hacienda Creeper, Mexican creeper, Senecio, and creeping fig. Is there anything I might do to encourage them to reattach themselves to the wall, or must I cut them back to the ground and wait for them to start over?

A: Cut them back, and they will grow back quickly to their original size. That is because they are already established.

Hacienda Creeper and climbing fig should climb up the painted wall again and reattach to the house on their own. These plants have established roots, so they should grow up the sides of the house quickly. Creeping fig is perhaps the slowest grower of the group, but it will re-establish itself over time.

Pull some of the stems toward the wall as they re-emerge, and they should start climbing. Cut off stems that don’t reattach, and those that do will climb faster.

Senecio and Mexican creeper are twining vines, so they will need some help climbing again. Adequate water, small amounts of compost once a year and regular fertilizer applications will push them to climb faster.

Q: I planted Roma, Better Boy and Early Girl tomato varieties this spring. Over 45 days later they’ve not gotten much bigger than when I brought them home from the nursery.

A: The weather has been colder and wetter than normal. That has slowed down the growth of warm-season vegetables such as tomatoes, peppers and eggplant. Be patient.

Hot caps aren’t used much anymore, but those along with Wall-o-water plant sleeves were made to speed up the growth of plants during cool weather. Rediscover these nifty little garden additions. They keep plants warmer and speed the growth of warm-season vegetables when weather is cool.

On the remote chance that something else might be going on, inspect some roots of these plants and see if there are any small “balls” growing on them. If found, that might indicate nematodes are in the soil and a problem.

Nematodes infesting plant roots can slow them down. There is not much you can do if they are present except replace the soil and plants.

That is one reason container gardening can be worthwhile. The containers can be sanitized and the soil replaced more easily than in a garden bed.

Bob Morris is a horticulture expert and professor emeritus of the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.

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