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.

Japanese anemone can be an attractive nuisance

We planted Japanese anemone a few years ago and it’s beautiful now that it’s blooming again, but it’s also spreading all over the place and taking over the garden bed! We’ve tried digging it up and cutting it back, but it just grows more. What can we do to keep it from spreading?

Here is an example of a plant that you can fall in love with once a year. The rest of the year, you may find you want to rip it out of the ground.

Japanese anemone has a lot to recommend it. It’s a perennial that grows in sun but is also happy in partly shady conditions. It doesn’t mind acid soil. The foliage grows tall (2 – 4 feet) in attractive mounds. Deer and rabbits don’t seem to care for it, and it blooms reliably in fall, opening masses of pretty white or pink flowers that sway in the breeze after summer-blooming perennials have given up for the year.

It’s a little finicky about soil; it requires good drainage and may languish during periods of drought, but the main complaint gardeners have is that it’s aggressive. It can take a couple of years for it to get established, but once it’s settled in and conditions are right, the plant spreads rapidly and forms dense clumps that take over whatever else might be in its way in the garden bed. Some have called it, generously, a “nuisance” plant.

Here in Zone 7a, Japanese anemone dies back after frost but it’s one of the first things to peek out of the soil in later winter, and once the weather warms, it takes off again. In my garden, it comes up through gravel paths, between rocks in a stacked stone wall, and is making its way into nearby raised beds in the kitchen garden.

It takes diligence and a sharp tool to keep it within bounds. Where you don’t want it to grow, dig it up. Try to get as much of the root as possible (which can be difficult, because the roots break easily). If you want to divide it to share with friends, spring is a good time for that task. Be sure to warn anyone who receives your gift of Japanese anemone that it can become an attractive nuisance.

The Betty Brown Tree Trail & Arboretum, Nashville’s first downtown arboretum, honors Elizabeth Moorhead Brown’s work to advocate for the city’s urban forests. Read the story in Saturday’s Tennessean.

Banishing ‘leaflets three’

QUESTION: What’s the best way to get rid of poison ivy?

Growing up where pavement and neatly trimmed lawn were the modern idea of landscaping, I didn’t encounter poison ivy until I became a real gardener. But by the time  I did learn the mantra (Leaflets three – let it be!) I knew to keep well away from it. Unfortunately, it seems to show up everywhere these days.

The best way to deal with poison ivy is, of course, to treat it very carefully. Fitzroy Bullock, a professor at Tennessee State University’s Cooperative Extension Program, has written a fact sheet on identifying the vine and dealing with it in the landscape.

When you find the sweet little seedlings in garden beds (often at the edges of the lawn, along fence lines, places that don’t get regular mowing), you can dig them out, roots and all, and dispose of them. Wear long sleeves and gloves to do the job. If you use disposable gloves, you can throw them away when you’re done, and avoid the possibility of accidentally getting the plant’s irritating oil on your skin. Some have suggested using a plastic newspaper bag as a glove, of sorts. Put your hand in the bag, use it to pull the vine out of the ground, then peel the bag off, inside out, with the vine inside.

If it’s a big vine with a well-established root system, it’s a bit harder to get rid of. Cut it as close to the ground as possible, and to keep it from growing back, immediately treat the stem with a garden herbicide that contains glyphosate (such as Roundup). Don’t spray the vine itself, and be careful not to let the spray get onto other plants, because glyphosate – or even a drift from the poison – will kill or damage most every green thing it touches.

Even after it’s dead, a large vine can be a problem. The toxic leaves dry up and fall on the ground, and later, after the aerial roots that have held it up begin to die, the whole vine could fall. Dispose of dead leaves and vines carefully, because the toxin is still present.

You may need to apply a second helping of herbicide if the vine begins to grow again from the stump. Apply herbicide again when the new, young leaves have opened fully.

If you are sensitive to the plant and accidentally make contact, expect intense itching, rash and blisters – not a serious situation, but certainly bothersome for a few days. It’s a good idea at any rate to wash your skin with soap and water after a day in the garden.