Easy Wave Gelato Mix petunia can be kept neat, tidy and full with a few snips now and then. Photo courtesy National Garden Bureau/ngb.org
As we move into the high season for planting, here are some tips and reminders for how to get the most out of our summer containers.
1. The larger the container, the better. Larger pots tend not to dry out as fast. It’s best to use containers that have drainage holes.
If you have a fancy container without drainage holes, plant your arrangement in a pot with holes that will fit inside the ornamental one. Place a brick, gravel, mulch or other material in the bottom of the ornamental container to keep the planted pot elevated so that it won’t be sitting in water.
2. Make sure plants in the same pot have the same horticultural requirements, such as sun or shade.
3. If planting a large ceramic, terra cotta or other heavy pot, place it where you want it before filling it with dirt and plants. Leave at least 1 inch between the soil line and the top of the pot. This space allows containers to be watered without displacing the soil.
Here are some more tips from the plant breeder Suntory, which includes brands Sun Parasol mandevillas, Million Bells calibrachoas and Surfinia petunias.
• Boost the number of shoots by trimming the branches that overflow the pot. Use scissors or pruners. This can be done two or three times during the growing season.
• Make sure the soil feels dry before watering. Overwatering leads to root rot or other fungal problems. Water the soil, not the plants. Water until the liquid runs out the bottom of the container.
• Fertilizer containers regularly, even if using a potting mix with fertilizer added or a slow-release fertilizer at planting time. Water-soluble products work well in containers. Always read and follow the label directions.
• Snip off spent flowers, called deadheading, to encourage plants to keep blooming.
• When plants start to look scraggly, give them a haircut. Cut the plants back to about 6 inches from the soil line. Plants will rebound in about two weeks. A lot of gardeners do this mid summer, when they leave for vacation.
When people ask about the best way to improve their gardens, I tell them to look down at the ground. The best gardens have great soil – soil that is a good blend of organic matter, microorganisms, air and clay, silt or loam.
The miracle ingredient is organic matter, such as compost, finely chopped leaves or well-rotted manure. Organic matter helps all kinds of soil, whether it’s clay, sand or loam. It improves drainage, yet helps with moisture retention. Organic matter feeds the soil’s microorganisms, which create the right environment for roots to thrive. Strong and healthy roots yield strong and healthy plants. The plants are better able to withstand stressful weather conditions, such as drought, and survive minor infestations of insects of diseases.
If you don’t make your own compost, you can buy it in bags at a garden center or you can get it by the yard, in bulk, from landscape suppliers. Between us, the stuff you get bulk is a much higher quality of compost than what you can get in a bag, which may be more convenient.
For existing plants, pull mulch aside, ring plants with compost and replace mulch. If there’s no mulch, add about an inch of compost across the bed.
When making a new garden bed, mix several inches of compost in the top layer. A 3-inch thick layer of compost also can be used as mulch around plants and over beds instead of bark or other materials.
• Avoid landscape cloth. Yes, I know it promises to reduce weeds. But once soil and other debris accumulates on top of the cloth, weeds can blow in and take root. I have pulled landscape cloth from many jobs and underneath, the soil is dry, compacted and without worms or microorganisms. Essentially, the soil looks and feels dead.
• Avoid synthetic fertilizers. They feed the plant, but do nothing for the soil. There also is some research that suggests synthetic fertilizers reduce worms and microorganisms in the soil. Instead, use fertilizers labeled as natural or organic.
• When making new beds, consider buying bulk planter’s mix from landscape suppliers. This is a mix of organic matter, topsoil, a little sand and other elements. Planter’s mix also can be used in raised beds.
• Avoid walking on garden beds. Compacted soil restricts root development and the movement of air and water.
For a full pot of shade-loving caladiums, plant several bulbs in a pot. Remove one or two node or eyes to encourage more stem and leaf growth. Photo courtesy Netherlands Flower Bulb Information Center
Finally, the weather might be cooperating enough that Hoosiers can begin some of the tasks of the season.
Fertilize trees and shrubs before they fully leaf out. Use an all-purpose fertilizer, such as Espoma Plant-Tone, Milorganite or other natural product. Read and follow the label directions, but usually the product is sprinkled around the base of the plant and watered in. Save a step by applying before a rain to let Mother Nature do the watering.
If you are fighting lawn weeds, apply a pre-emergent herbicide, such as corn gluten, when the forsythia blooms. A pre-emergent does not kill existing weeds. It keeps weed seeds from sprouting. However, if planning to sow grass seed, hold off on the pre-emergent because it does not distinguish between grass seed and weed seed.
Even though you’d like to kill dandelions and other perennial weeds in the lawn, the best time to do that is in late summer. Applying an herbicide now will cause plants to curl, which might make you feel better, but it’s only a temporary set back for the weeds. The reason to treat perennial lawn weeds later in the season is because the plants are bulking up for winter survival, which makes the herbicide more effective.
Want more perennials? Divide them, especially if their flower power has diminished over the last few years. Dig up the plant and use a bread knife, Japanese soil knife or a sharp spade to divide the clump into a few sections. Plant the divisions. Dividing summer-blooming perennials now allows them to get well rooted for their seasonal show. You can also fertilize perennials as they emerge from their winter sleep, or apply a light layer of compost around the plants.
This is the time to pot up cannas, caladiums and tuberous begonias indoors so they will have some size and be ready for planting outdoors once the air and soil temperatures warm up in mid May. To boost the fullness of caladium, dig out one or two nodes or eyes on the bulb before planting.
Sow seeds for warm-season vegetables, such as tomatoes, peppers and eggplant, indoors. You will likely need to use supplemental lighting for these seedlings. Keep the lights a couple of inches above the seedlings, raising the lights as the plants grow.
It’s time for ready, set grow!
When planting a grafted tomato, keep the graft at least 1 inch above the soil surface. © Jo Ellen Meyers Sharp
Last year, grafted vegetables, especially tomatoes, showed up on garden center tables. It’s not the term grafted that attracted people’s attention as much as the cost, frequently three times what you’d pay for a regular tomato in the same size pot.
We’ve been planting grafted plants, such a tea roses and apple trees, for centuries. In the 1920s, the Japanese and Koreans started grafting vegetables, especially tomatoes and other plants in the same botanical family. Interest started here in the United States in the 1990s.
The grafting process is pretty much the same, whether it’s an apple tree or a tomato.
A grafted plant has two parts, rootstock and scion. The rootstock is selected because it provides disease resistance, boosts production or has other characteristic that support the top part of the plant, called the scion. The scion is selected for the taste, size of fruit or other attributes it produces.
Under laboratory-like conditions, the two pieces are grafted together and held in place with a clip or other device until the wound heals.
Last year, I grew a grafted Black Krim and a regular Black Krim heirloom tomato side by side. I wish I could report some observation other than last year was a terrible tomato year for me.
The grafting process is of particularly interest with heirloom tomatoes, which lack disease resistance and mature late. A grafted heirloom tomato would have the disease resistance we want and better and earlier production. I’m going to them again this year with Brandywine, another heirloom.
A lot of savvy gardeners remove all but the upper-most leaves and plant their tomato transplants deep in the soil, or to dig a trench and plant them horizontally. This encourages good root development along the stem that is underground.
However, you can’t plant grafted tomatoes this way. The graft, usually marked with a plastic clip, must stay at least 1 inch above the soil surface. If the graft is below the soil grade, stems from the rootstock will emerge and overwhelm the scion, defeating the purpose of graft.
This labor-intensive process is why the cost of grafted vegetable plants is so much higher. But, if production is boosted considerably, you could get by with fewer plants, something that might offset the cost. Or, you can splurge on one grafted tomato and grow it side by side the same type of regular plant and do your own little experiment.
Snowdrops are one of the earliest bulbs to bloom. When they emerge in late winter and early spring, they signal the new season. (C) Jo Ellen Meyers Sharp
I don’t know about you, but about everything in my garden is flat. Flat, flat, flat. The perennials, some small shrubs and the lawn.
This time of year is always the big reveal — which plants made it through winter and which ones didn’t. But this past winter, which buried plants under snow for months, may delay seasonal signs of life.
There are a few signals, though.
I’m joyous about the common snowdrops (Galanthus nivalis), which are the first bulbs to emerge in spring. I planted these tiny bulbs last fall and have been rewarded with tiny, bell-shaped green and white flowers dangling from stems just a few inches above the soil this spring.
I trimmed off all the brown, dried leaves on the hellebores (Helleborus). I learned this trick last year when I spoke at the Northwest Flower & Garden Show in Seattle. All the hellebores had their winter-damaged leaves snipped off, which made the flowers much showier.
The coral bells (Heuchera) like to wriggle out of the ground in winter, heaved from the soil by freezing and thawing. I just tamp these perennials back into the ground. This is a good time to trim off winter-damage leaves on these beauties, too.
Last week, I corrected a mistake. A couple of years ago, I’d planted yellow-blooming crocus (Crocus) in the lawn. When they bloomed, from a distance they looked like dandelions. I have enough of those already, so adding similar-looking flowers was not a smart move. I transplanted them from the lawn to under the gingko tree (Gingko biloba).
As with many landscapes, the trees planted years ago have grown to cast a lot of shade in what used to be sunny spots in the landscape. Besides the shade, the river birch (Betula nigra) is just too messy over my neighbor’s driveway, so I’m going to have it removed. I think I’ll transplant a serviceberry (Amelanchier x grandiflora ‘Cole’s Select) that I’ve had for about 20 years to the area where the river birch was. Where it is now, the serviceberry is leaning away from the honey locust tree (Gleditsia triacanthos inermis) toward the sun.
In the backyard, a weedy mulberry (Morus) shades the vegetable garden, so it is going, too. When it’s gone, the Jim Wilson sweetbay magnolia (Magnolia virginiana ‘Moonglow’) will be so much happier with some morning sun. So will the veggies.
The list is long and the time is short, but it gives this gardener’s soul something to look forward to.
Most hybridized fragrant hosta have Hosta plantaginea blood. Photo courtesy of PerennialResource.com
Lack of water at the right time is the primary reason hostas don’t do well in our gardens.
In particular, water hostas in July, August, September and October and keep watering until the first frost, said Cynthia Miller Wilhoite, who has been growing Hosta for 35 years and has more than 800 cultivars in her collection. An active member of the American Hosta Society, she and her husband, Chris Wilhoite, own Soules Garden on Indianapolis’ southside. She spoke earlier this month at the 20th annual Spring Garden Clinic.
The most common pest of hostas is the slug and the best control for this leaf-munching, land mollusk comes from the sea — crushed oyster shells. This common feed for chickens is usually available at farm stores.
Apply a ¾-inch deep layer of crushed oyster shells in a 6-inch-wide ring around the leaves, called pips, as they emerge in spring. She said this one application of this natural product is all that’s needed to control slugs throughout the growing season.
Variegated hostas tend to grow more slowly and may not always be the toughest. That’s because the white or cream variegation lacks chlorophyll, the pigment that turns sun into plant energy, she said.
“I tend to like hostas with a thicker leaf,” Wilhoite said. Not only are the plants generally tougher, thicker leaves also provide more slug resistance. Always consider the mature size of the plants. Hostas may take up to seven years to reach maturity.
The popularity of mini hostas is fueled by consumer interest in miniature gardens. Miniatures usually are not larger than about 12 inches tall and wide, some with leaves as small as a thumbnail. Minis also are good as an edger in the shade garden.
Wilhoite said medium-size hostas are the workhorses in the garden because they provide a good show without overwhelming the scene. These will be 12 to 18 inches tall and no wider than about 2 ½ feet. Large and gigantic hostas will be at least 4 feet wide or more, she said. Here’s a sampler of her recommendations:
- Blue Mouse Ears
- Itty Bitty
- Itsy Bitsy Spider
- Mini Skirt
- Church Mouse
- Pure Heart
- Autumn Frost
- Mystic Star
- First Frost
- High Society
- Sum and Substance
- Blue Angel
- Earth Angel
- Blue Mammoth
- Empress Wu
- Moonlight Sonata
- Royal Wedding
- Stained Glass
- Cathedral Windows
Ultimate Mixed lettuce. Photo courtesy of National Garden Bureau
Since this is the best time to think about what edibles we will grow this year, I reached out to area gardeners about what they are planning. Last week, we talked to gardeners who planted less familiar foods: tomatillo, leeks and celeriac. Today, the gardeners’ menu is more mainstream.
Lettuces and Greens
Marion County Master Gardener and graphic designer Karen Kennedy wishes she had enough sun to grow vegetables successfully.
“I do successfully grow leaf lettuce along the edge of one of my perennial beds,” said Kennedy, who sows packets of seeds of mixed salad greens. “The area gets a nice mix of sun and shade and, depending on how fast we go to high heat, I can sometimes keep it going until mid June, or early July. I’ve also grown rainbow chard in one of my perennial beds.”
German Johnson heirloom tomato. Photo courtesy of Bonnie Plants.
Like a lot of Hoosiers, Carol Michel, an Indianapolis south sider and award-winning blogger at maydreamsgardens.com, picked tomatoes as her must-have veggie. “They truly do taste better when they are homegrown. I like the variety German Johnson. It’s an heirloom that tastes like a tomato should taste and the fruit is so big, that you just need just one slice to cover an entire piece of toast for a BLT,” she said.
After all, it’s a family tradition.
“The thing about the German Johnson tomato is that my grandfather was German and my grandmother’s maiden name was Johnson, so I always think of them when I grow this tomato,” Michel said. “I am to the point where I have to grow it or my garden feels incomplete.”
She grows them in the ground. “Plant it deeply in a sunny location and water when we don’t get rain. Provide strong staking because it will be big plant.”
Red Norland and Yukon Gold potato harvest. (C) Photo courtesy of Sally Zelonis
The best part of growing potatoes is harvesting them, said Sally Zelonis, major gifts officer at the Indianapolis Zoo. “It’s like panning for gold! When you carefully dig in the ground to see what you have — it is so fun to pull up a beautiful potato,” she said.
She buys seed potatoes at The Garden Center on Indy’s northwest side. She purchased cloth tubs online for growing her potatoes because her Zionsville, Ind., yard is very small. She hand picks any insects from the plants. Periodically, she grows several varieties of potatoes and relishes their many colors. “When I harvested them, I made homemade French fries with each variety to try them out. What fun,” she said.
Tomatillos are the main ingredient in salsa verde. (C) uckyo/dollarphotoclub
As we wait for the big thaw and the dry out, I thought it would be fun to check with some gardeners throughout the area to see what vegetables they are dreaming about. Next week we’ll explore more common vegetables. Here are some less common faves:
Last summer Ginny Roberts planted Botanical Interests’ Tomatillo Toma Verde, an heirloom. “Tomatillos are very easy to grow, hardy and prolific,” said Roberts, urban garden program assistant at Purdue-Marion County Extension.
“My husband and I enjoy using them in a variety of fresh salsas. We also make a wonderful sauce and freeze it. And, much to our pleasure, bees flock to the flowers until late fall.”
Tomatillos grow similarly to tomatoes, but are related to gooseberries. (C) ason/canstockphoto
Roberts started plants from seeds indoors and transplanted them outdoors. “I planted 18 and learned the hard way that they are heavy producers and can become space hogs. I will plant just six this year and fence them in. End of season clean up should include raking up any dropped fruit. Tomatillos will reseed, if given the opportunity!”
Leeks are easy to grow from seeds. Some garden centers and online retailers may have starts. (C) Max Straeten/morguefile
Beautiful leaves and harvesting-as-needed make leeks attractive to Chris Turner, owner of uTopos Gardens, an Indianapolis gardening company. “I am not so good at harvesting vegetables that are time sensitive, such as tomatoes, so anything that can wait for me is my kind of vegetable!”
Sowing seeds was easy and less expensive than buying starts. “I put all the seed in one pot, and then teased the seedlings apart when it is time to plant in the garden,” he said. In the garden, he digs a 3-inch deep trench and sets the leek seedlings in the bottom. “As they grow I push the dirt back into the trench around the plants. This makes for longer white parts.”
“I like growing less common vegetables, and last season I enjoyed growing celeriac. Sometimes celeriac is called celery root,” said Fritz Nerding, manager of the Garfield Park Conservatory and Sunken Garden. “I grew the Diamant variety from John Scheepers Kitchen Garden Seeds. He sowed seeds indoors in February and transplanted seedlings outdoors about 12 weeks later.
Celeriac has a celery-like flavor. (C) ccat82/canstockphoto
He grew celeriac in rich garden soil amended with mushroom compost and rotted manure. “Celeriac requires more water than most garden plants, but the extra watering rewarded me with a fantastic celery-root stuffing for our Thanksgiving turkey.”
Here’s HortusScope for March 2014, a checklist of garden and nature related events compiled as a public service by Wendy Ford of Landscape Fancies. Please click on the link below to download your copy.
HortusScope March 2014
Cinnamon Snow hellebore. (C) Jo Ellen Meyers Sharp
Granted, snow is nature’s best insulator, but some gardeners are wondering about the perennials that retain their leaves through winter.
Coral bells (Heuchera), hellebores (Helleborus), thyme (Thymus) and some of the ground cover sedums, such as ‘Angelina’ (S. rupestre), have spent weeks under several inches of snow, deprived of light.
Gardeners are nothing if not optimistic. Once the snow melts and spring rains subside, snip off any brown or damaged leaves, or in the case of sedums, the stems.
Hellebore flowers are a lot showier when winter-damaged leaves are cut off. Coral bells tend to be heaved from the ground in winter, so gently push the plants back into the soil. Avoid walking on wet soil, though. Doing so compacts the soil, making it harder for roots to thrive.
Don’t be alarmed if the tips of some of the emerged leaves of tulips, daffodils and other spring bulbs are a bit yellow after the snow melts. They will likely green up once exposed to light.
L.F. of Indianapolis emailed me in search of a tall, blue, late-blooming campanula named ‘Border Blues’ (C. lactiflora). She was looking for the perennial plant or seeds and wanted a local source, but we could not find any. Even online, this plant, a Darwin Perennials introduction from Ball Horticulture, could not be found from a retailer who would ship to Indiana.
“I know it seems silly to try to get a specific plant when so many others are available, but, well, you know gardeners!” she wrote.
So, what’s a gardener to do? First, check with your independent garden center, where staffers will try and locate a plant. If it can’t be found this year, ask the garden center to find it for next year or to order it specifically grown.
Many garden center employees attend a couple of trade shows each summer: OFA in Columbus, Ohio, in July, and Independent Garden Center Show in Chicago in August. These huge shows have dozens of new plant introductions amid thousands of products and services on display. Try to reach out to garden centers about the plant(s) you can’t find before the shows, so employees can be on the lookout.
Sometimes, the plants will not be available locally, so look online. There are many reputable online plant retailers. Usually you can search a site or peruse a catalog online for specific plants or seeds.