April Garden Tips & Tasks

Spring — however capricious it may be — has arrived, and it’s time to head back outdoors, keeping an eye on the weather. Gardeners in Middle Tennessee — Zone 7a, where The Garden Bench calls home — are anxious to get the season started. Warmer areas are already in full swing; if it’s cooler where you are, it’s getting close!

If you live in Middle Tennessee, there are a couple of good garden events to look forward to — both live this year! The annual Perennial Plant Sale sponsored by the Perennial Plant Society of Middle Tennessee will be held Saturday, April 9, 2022. The Herb Society of Nashville’s annual Herb Sale will be Saturday, April 30, 2022. Both will be at The Fairgrounds Nashville’s Expo 3 Building. Details are in the sidebar, or visit the organizations’ web sites. The annual Herb & Craft Fair sponsored by First Unitarian Universalist Church of Nashville will be Saturday, April 23, 2022, 9 a.m. – 3 p.m.

Here’s what else is on your garden to-do list for April.

Early this month

Did your hardy herbs survive winter? Trim dead foliage of sage, rosemary, thyme, oregano and other cold-damaged herbs. Replant those that didn’t make it through the freezing weather.

Trees and shrubs planted in spring need plenty of water during the first year of growth, especially as the weather gets warmer.

Set out hummingbird feeders to welcome the birds back to your garden. Hummingbird nectar recipe: one part sugar to four parts water. It’s not necessary to use red food coloring.

Plant your favorite herbs: parsley, sage, thyme, rosemary can be planted early in the month. Basil and dill are more tender herbs, so wait a bit longer to be sure the weather is warm enough.

To have a big display of flowers in summer, sow seeds and plant summer-flowering bulbs in April: zinnias, sunflowers, cleome, cosmos and other summertime favorites.

Mid-April

Get rid of weeds while they’re small and easy to pull. Use mulch to keep weed growth (and weed-pulling) to a minimum.

Mid-April marks the official last-frost date in Middle Tennessee, and it’s usually safe to set out warm-weather bedding plants such as petunias, coleus and begonias, and vegetable transplants — tomatoes, peppers, eggplants. But keep an eye on the weather. Spring is unpredictable!

Sow seeds of okra, cucumbers, squash, beans, melons, and other kitchen-garden favorites.

Don’t skimp on mulch. Use it to keep weed growth (and weed-pulling) to a minimum, and to help keep the soil moist in annual, perennial and vegetable beds.

Remove the dead flowers and stalks of daffodils, tulips and hyacinths, but leave the foliage until it turns yellow. This is the time spring-flowering bulbs build up energy to bloom again next year.

Later this month

If you don’t have space for a kitchen garden, at least plant herbs in a pot. Some favorite container combinations for cooks: parsley, basil and thyme; rosemary sage and chives; mint, basil and dill. Remember to water containers frequently as summer weather approaches.

The best time to prune azaleas, flowering quince, forsythia, lilac and other early-flowering shrubs is right after they finish blooming. These plants begin forming buds for next year’s flowers on this year’s growth.

Many houseplants thrive in shady, protected spots outdoors. Place them where they won’t get blown by strong winds, pelted by hard rain or disturbed by marauding animals.

If you plant shrubs and trees this spring, make sure they get plenty of water during their first year of growth, especially as the weather gets warmer.

Provide about an inch of water a week to lawns and garden beds.

May garden tips & tasks

May is a busy and beautiful time in the garden. Here are tasks and tips to keep you busy this month.

Early in the month

If you haven’t already gotten those warm-season vegetables in the ground, plant them now! Tomatoes, peppers, squash, okra, beans, eggplant and other favorites will get off to a fast start now that the weather is warm.

Set out bedding plants of zinnias and other summer annuals.

Set out bedding plants of zinnias, celosia, snapdragon, begonias, petunias, coleus – all the favorite summer annuals.

Plant plenty of basil in a sunny location to use in summer recipes. Clip and use it frequently, which allows the plants to grow sturdier. Snip off flowers as they begin to form.

Prune roses for better blooms

We have a rose bush that is out of control and really needs pruning. Can it be done now? Or is it better to wait until next spring?

Rose experts say that roses can be pruned anytime they are actively growing. Start by trimming out the older wood first, along with any dead or dying canes. You may also want to remove canes in the center of the bush to provide better air flow, any canes that cross and rub each other, or any twiggy growth that might be tempting to spider mites.

The Nashville Rose Society provides general pruning guidelines: each pruning cut should be made about ¼-inch above an outward-facing bud eye (where the leaf is attached to the stem). Use sharp bypass pruning shears, which will make a clean cut without crushing the stem.

An added tip: remove the spent blooms of roses regularly to encourage the plant to bloom more.

Serious rose growers may do a more severe type of pruning in the fall to winterize bush roses. Nashville Rose Society also provides general guidelines for this process: Stop fertilizing roses early in August to allow the plant to slow down producing new growth, then in early October, stop cutting off the dead flowers. In late November or early December, cut the canes back to 2 to 3 feet and place a mound of mulch around the bush.

Next spring, once the weather begins to warm up, move the mulch away from the roses and prune to about 12 inches to get new growth.

In Saturday’s Tennessean

The Ernest and Berdelle Campbell Land Trust Garden is a quarter-acre oasis in Nashville’s tightly-packed Germantown neighborhood. “This will always be green space,” Berdelle Campbell says. Read about the garden and Berdelle’s agreement with The Land Trust for Tennessee in Saturday’s Tennessean, and find more here about my visit with Berdelle, and more photos from the garden.

Free daylilies!

A Middle Tennessee reader emailed last week to say that she has a back yard full of daylilies that she can no longer take care of, and she is trying to find a home for them. “There is a huge assortment in lots of different colors and types, mostly full size but some miniatures,” she wrote. “My grandmother and mom collected them over the year and I don’t really know any of their names.”

If you are looking for daylilies, are willing to take a chance on sizes and colors, and can dig them up yourself, she is willing to donate. Interested? Email me at gloria@gloriaballard.com and I will put you in touch.

Fortunately, the best time to dig and divide daylilies is coming up. I wrote about how to do that task here.

Prune crape myrtle without committing ‘crape murder’

I have developed my crape myrtles into tree forms. Every year I have to cut back the suckers that grow from the base of the trees at ground level. Is there anything I can do to eliminate the suckers?

The suckers that grow from the ground around crape myrtles can be the result of improper pruning. If you top the plants every year (and garden experts sometimes refer to this as “crape murder”) they respond by sending up shoots from the base.

There are many sources for information on pruning crape myrtles, but one good one comes from the Virginia Cooperative Extension of Virginia Tech and Virginia State University. Their suggestion:

Prune crape myrtles as you would any other tree or shrub – by cutting back to a bud, a side branch or a main stem, giving consideration to the ultimate shape of the plant. If you need to cut off only part of a branch, cut above an outward facing bud or side branch. If you need to remove an entire branch, cut just outside the branch collar on the stem, where the branch is attached.

Don’t make random cuts in the middle of a branch or stem. Topping a crape myrtle – or any tree, for that matter – can lead to stem decay and more dead branches. It also encourages the growth of weak shoots at the top of cut stems, which can become top-heavy with flowers and break in a strong wind.

The Virginia Cooperative Extension notes that re-suckering can sometimes by suppressed by applying naphthalene acetic acid after the suckers are pruned. Crape myrtles that are given too much fertilizer may also produce suckers, and have fewer flowers. They advise not to fertilize unless a soil test indicates the need to do so.

The best time to prune crape myrtles has passed for this year. Do the job in late winter or early spring, before new growth begins.

 

This weekend: Beautiful bonsai

Bonsai expert Owen Reich invites garden enthusiasts to the Nashville Bonsai Society’s Regional Bonsai Expo July 11 – 13 at Cheekwood Botanical Garden. Reich, Jim Doyle and Young Choe are guest artists, and there will be more than 50 bonsai displays, along with workshops, exhibits and vendors.

The photo above is of a Swamp Rose (Rosa palustris) that Reich collected in Tennessee and trained as a bonsai. “There will be a number of bonsai on display this year created from trees and shrubs native to the United States, as well as high-end bonsai imported from Japan,” he says. The stand in the display was made in Chattanooga by Tom Scott, and the container is a 250 – 300 year-old Chinese container called a Kowatari Shirogochi Pot.

The picture is just a sample of the unique and unusual bonsai on display this weekend. Complete details here.

For mums, just a pinch

QUESTION: I bought pots of mums last fall and planted them in the ground after they finished blooming. They died back over the winter, but grew back this spring. I’ve heard that they should be trimmed after they start to grow, but how much should they be cut?

Those ubiquitous pots of cheerful chrysanthemums that appear in garden centers in late summer are referred to as florists mums. Planted in full sun in good, well-drained garden soil, they should indeed return year after year.

The shoots can begin to appear early in spring. Garden experts advise pinching off the tips of florists mums after they reach 5 – 6 inches tall. As they continue to grow, keep pinching, nipping off the top pair of leaves, throughout the spring and early summer to encourage more lateral growth (making the plants fuller and bushier). This will also delay flowering until late summer and fall, when these bright spots of color will be welcome in the garden.

Keep pinching until about mid-July, then allow the plants to begin to form buds, which will start to flower as fall approaches, about the time many other things are beginning to shut down.

Mums seem pretty resilient. In my own garden, which is more dappled sun and shade than full sun, the mums quickly grow tall and rangy, and I cut them back more severely – sometimes as much as three or four inches off the tops of the plants (I’ll give them a final trim this week). Still, they continue to grow tall, and flop over to cover the garden in a patchwork quilt of colors each fall.

Give mums a trim now … or later

Question: In your opinion should chrysanthemums be cut back in the late fall or spring?

Different sources say different things about what to do with mums after they are browned by frost. One source advises to cut them back in the spring; another says to cut them back to about 8 inches after they finish blooming in the fall.

In my experience, either way seems to work. I usually leave them until spring in my garden beds, which tend to be informal (some might call them “messy”), and often the new leaves start to come up from the roots very early — as early as February, if we have a mild winter. At that time, I cut back all the dead stems and divide and move clumps where necessary, and they grow happily and vigorously through the spring and summer. I cut them back a couple of times during the summer to delay flowering, and they start to bloom in the fall.

If you prefer a tidier look throughout the winter, cut off the blooms after they turn brown. They will rest during winter and be ready to pop up again early next spring.