Planting time, a soil “squeeze test,” and how to plant a shrub: This Weekend in the Garden

The end of March is the beginning of the main planting season here in southcentral Pennsylvania, a time when it’s fine to start planting most trees, shrubs, evergreens, and perennial flowers.

The best new trees and shrubs of 2019

Smaller, tougher, and longer-blooming are the traits of many of 2019's best new trees and shrubs.

However, late March and early April are often muddy times, as melting snow and spring rains conspire to turn garden soil into sticky slop.

Don’t ruin your soil structure by digging too soon. Working and walking on wet soil forces out air particles and leaves you with something akin to concrete.

This potential pitfall can vary a lot depending on your soil and where you’re digging.

If you’ve been blessed with well drained soil and have been careful to avoid planting in low-lying depressions, you’ll be able to get an earlier start than the gardener with clay, poor drainage, a lot of low spots, and/or a high water table.

This is also where raised beds really benefit. By adding compost or other organic matter to “fluff up” your beds to a few inches above grade, you’ll keep those plant roots out of the sogginess.

One simple test tells you whether the soil is dry enough to dig -- pick up a handful of soil and squeeze it. If it crumbles when you release it, you’re good to go. If water drips as you squeeze, or if it’s a solid, sodden ball when you open your hand, wait until it dries before digging.

It’s fine to dig damp soil but not fine to dig wet or soggy soil.

While you’re down there grabbing the soil, that’d be a good time to collect some for a soil test.

Do-it-yourself, mail-in Penn State soil test kits are available for $9-$10 from county Extension offices, many garden centers, and online at Penn State’s soil test lab.

By mailing in a composite sampling from a dozen or so areas, you’ll get back a report telling you what kind of fertilizer you need, how much, and whether you’ll need to adjust the soil pH (a measure of its acidity level).

The best new perennial flowers of 2019

Some of 2019's top new perennials feature a beautiful blooming onion and several stunning new succulents.

If roots are tightly matted or circling like these, they should be frayed out or even cut before planting.

How to plant a shrub

If you’re investing in new plants â€" especially more expensive ones like trees and shrubs â€" it pays to know how to plant them correctly.

You can stunt and even kill woody plants by planting them the wrong way. Planting too deeply and misfiring with the water (either too much or too little) are the most common plant-fatal mistakes.

Here’s a quick rundown on the process:

Dig a hole at least three to five times as wide as the root ball but no deeper than the root ball’s height.

Mix the excavated soil with 10 to 20 percent compost or similar organic matter. If your soil is reasonably good and not compacted clay or subsoil, skip this.

For container-grown plants, remove the plant from the pot, and fray out the roots, especially if they’re circling. It’s OK to disturb or remove some of the soil to do this. If you can’t free the roots by gently pulling them, make three or four vertical cuts in the root ball to break up the tight mat.

For plants that come with their root ball wrapped in burlap, set the shrub in the hole, and cut off and remove as much of the burlap as you can after setting. Also cut apart or remove any wire baskets and any rope or strings tied around the trunk or roots.

For plants grown in nursery pots, set the loosened root ball on solid ground at the bottom of the hole so that the crown of the plant (where the emerging stems transform into the roots) is sitting an inch or two above grade. Remove or add soil to adjust to this planting depth. Do not plant with the crown below grade.

Adjust the plant so the “good” side (if there is one) is facing the way you want. Check the plant from all angles to make sure it’s in the ground straight. Backfill halfway with soil, tamp, recheck for straightness, water, then finish backfilling and tamp again.

Cover the ground with two to three inches of bark mulch or wood chips and then water again.

From then on, your main job will be keeping the soil consistently damp throughout the first season. For trees and shrubs, it’s better to give them a deep soaking about twice a week (rather than more frequent light waterings) so the soil is damp all around and to the bottom of the root ball.

For trees, staking is not necessary unless you’ve planted a rather large tree with a comparatively small root ball, or if you’ve planted on a slope or in a windy area.

If staking is needed, hammer two or three stakes in the ground, and secure the tree with a wide band or strap at chest to shoulder level. Tie securely but not so tight that the tree can’t move at all. Don’t use wire or rope, which can cut into the bark.

After no more than one year, the staking should come off.

These roses have arrived by mail-order without soil, i.e. “bare root.

Planting bare root

Another way you might find new plants is “bare root.

This is when plants are sold without soil. It’s mainly done as a way to hold down shipping costs, and is usually how you’ll get plants bought online or by mail-order.

Bare-root plants are mainly sold at the beginning of a new garden season since they survive best shipped when they’re still dormant.

Bare-root tree, shrub, or rose planting is similar to planting a container-grown plant but with a few exceptions.

One is that most bare-root plants do best when their roots are rehydrated by soaking them in a bucket of water for a few hours or overnight. That’s usually spelled out in the planting directions.

Prepare your hole the same way as described above, but when you’re ready to set the plant, create a little mound under the trunk and spread the roots down it.

As with container plants, be careful with the planting depth. Locate the crown and be sure it’s two to three inches above grade by the time you’re done backfilling.

Once you’ve gauged that height, fill the hole with excavated soil, tamp, water, and mulch as described above.