Kerry Heafner, Singh, Raghuwinder, Strahan, Ronald E., Fontenot, Kathryn, Kirk-Ballard, Heather
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Springtime in the ArkLaMiss usually means it’s time to plant Irish potatoes in the vegetable garden! The LSU AgCenter recommends Red La Soda, Norland, La Rouge and Red Pontiac for red-skinned varieties and La Chipper, Norchip, Atlantic, Kennebec, La Belle and Yukon Gold for normal-skinned varieties for Louisiana home vegetable gardens.
Irish potatoes are tubers, which are underground stems modified for starch storage. The “eyes” are where new, aboveground (lateral) branches will sprout from. Local hardware/feed stores will carry seed potatoes, which are whole potatoes used specifically for growing new plants. Cut large seed potatoes into 2-ounce pieces containing at least two viable eyes. Because wet soil may cause seed potatoes to rot in waterlogged soil, some sources recommend coating the cut ends with agricultural sulfur prior to planting. This is not necessary for soil with good drainage. Plant Irish potatoes in rows spaced 4 to 6 feet apart in friable soil. Plant pieces of seed potato 3 to 4 inches deep at 12-inch intervals. As plants grow, hilling soil around them periodically will be necessary to create more underground space for tuber formation and to completely cover tubers that have already been formed. Tubers are forming underground about the time aboveground stems flower. The crop is ready to dig when plants start to yellow and die off. Start digging for tubers about a foot on either side of the plants, then work inward toward the center of the row. Potatoes that are injured during digging should be used immediately. Otherwise, gently brush away any loose soil and store them at about 55 degrees in a humid area until ready to use.
Kerry Heafner
Associate Extension Agent in Horticulture
Brightly colored bags for fertilizer, weed-and-feed, and other products for lawns are now on display in garden centers across the region. But just because all those products for lawns are out doesn’t necessarily mean they need to be applied to your lawn. If fact, if your goal is to establish a new lawn, start with the most basic, elemental part: the soil. If your soil hasn’t been tested in at least three years, it’s time to have that done. Because soils throughout most of the southern U.S. tend to be acidic (below pH of 7), the need for a lime application should come as no surprise. Remember that, when it comes to pH, you’re shooting for a range and not an absolute value. Both common and hybrid Bermudagrass as well as zoysia need a soil pH ranging anywhere from 5.8 to 7.2. St. Augustinegrass needs a pH ranging between 6.0 and 7.2. Centipedegrass will need a slightly more acidic (lower) pH range, anywhere from 5.0 to 6.0. Results of a soil test will make a rate recommendation for lime if soil pH needs to come up significantly for a new lawn. Ideally, lime should have been applied back in the fall. But, if it is needed, don’t wait to get lime applied now; the earlier the better.
Soil test results will also indicate whether fertilizers need to be added to replenish nutrients. Of the three numbers on the fertilizer bag, the first number is the number of interest. The higher that number is and more fertilizer applications you make, the more you’re going to be mowing! Nitrogen is a very mobile nutrient. Amounts in the soil will differ from nitrogen levels in the roots, the stems, the leaves and so on. When lawns have come fully out of dormancy, resume fertilizer regimens and apply no more than 1 pound or 2 of nitrogen per 1,000 square feet.
Kerry Heafner
Associate Extension Agent in Horticulture
If seed potatoes are still to be had, Irish potatoes can still be planted into April with no ill effects. Everybody says plant potatoes by Valentine’s Day, but the potatoes don’t know when February 14 is! Planting potato pieces in warmer soil will lessen the risk of the eye pieces rotting. Sweet corn can be planted in March. Three types of sweet corn varieties are available based on sugar content of the kernels: normal, sugar-enhanced and super sweet. Super sweet varieties should be protected from cross pollination from other varieties by being planted anywhere from 25 to 200 feet away from other varieties. Because it is pollinated by wind, sweet corn should be planted in a multirow block instead of in a single, long row.
Vegetable seeds that can be sown during spring include snap beans, beets, carrots, greens, English peas, radishes, lettuce, spinach and early maturing watermelons. Transplants of broccoli, Brussels sprouts, cabbage, cauliflower and Swiss chard can go into the vegetable garden in early spring. Both hybrid and open-pollinated varieties will perform well in our region, and don’t be afraid to try some new varieties. Sugar Snax, Yellow Bunch, Deep Purple are carrot varieties that performed well in LSU AgCenter trials. Rubicon, OS Cross, Megaton and Grand Vantage are cabbages that performed well in 2015 LSU AgCenter trials. Look for these varieties in both seed catalogs and local retail outlets. For cole crops, a spritz with a suspension of Bt will ward off caterpillars of the cabbage looper moth. Pay special attention to the undersides of leaves. However, nocturnal attacks by cutworms can be problematic. If you find chard plants laid over on the ground when you visit the garden during the day, try going out at night with a flashlight to catch cutworms red-handed. Pick the worms off the plants and drop them in a can of soapy water. Problem solved.
Seedlings of tomato, hot and sweet pepper, and eggplant that were started in February will need transplanting to either six packs or 4-inch pots in March. Take advantage of mild, sunny days to harden off seedlings by bringing them outside in partial sun during the warmest part of the day. Take them back inside for the evening. If using a hotbed, raise the lid during the day, then close it again in the evening. Gradually introduce them to full sun as they grow. Prepare their places in the vegetable garden now by incorporating compost or well-rotted manure into the soil. Seeds of squash, cucumbers and mid- and late-season watermelons can be started indoors now for transplanting out to the garden throughout spring. Generally, these vegetables germinate in a week and should be transplanted after the first true leaf is produced. Transplants should not become root-bound; roots of these and other cucurbits are easily damaged. Try both straight and crook-neck varieties of yellow squash. Cosmos and Cheetah were top performers in 2015 trials conducted by the LSU AgCenter. Don’t forget patty-pan squash. This gardener finds them to be superior in flavor. A friable, well-drained, organic soil is best for any type of summer squash.
Continue to build compost piles this spring. Harvest finished compost and either add directly to beds or store it in plastic bins that have had holes drilled in the side for aeration. Plant-based scraps from the kitchen are perfect composting material, especially when combined with fallen leaves from back in the fall. Keep compost piles moist so microbes will remain active.
Kerry Heafner
Associate Extension Agent in Horticulture
You don’t need a large yard or a lot of space to create a beautiful garden. You can create beautiful planters or containers that fit any space with limitless plant combinations that bring beauty and joy to wherever you call home.
There are plenty of options to choose from when it comes to the size, shape and color of containers and planters — hanging baskets, window boxes, small and large containers for combination plantings, single plant containers and clusters of pots. Your options for the plants themselves are plentiful and diverse, too.
To create a beautiful container design, begin by choosing a container that suits your spatial needs. Most garden centers, retail nurseries and online shopping venues offer many types.
Next, choose the plants and arrange them in a design of your choosing. Keep them looking good until you want to change the design.
One of the great advantages is that you can change these out. Year after year, you can play with the plant combinations, colors, textures and themes.
A combination planter typically has what is known as a filler, a thriller and a spiller. If you haven’t heard these terms yet, let me explain them to you.
The thriller is the plant that is main attraction of your container planting. It will be the focal point of your design. Choose a plant that has some height and a striking flower form or color.
The filler is just as the name suggests. Use these plants to fill in areas to create a fuller look in the arrangement. Fillers are medium-sized plants, typically in a mounded form, that make up the bulk of the plant material in the container. You can choose just one type of plant for focal impact, or you can choose several different plant types of similar sizes.
Spiller plants are the trailing, cascading plants that flow over the sides of the containers and complete the arrangement.
When choosing fillers and spillers, a good rule of thumb is to use an odd number of plants — three, five, and seven and so on.
Symmetry brings a good balance to beginning designs. Although it is not required to have an equal number of similar or identical plants on each side of the focal point, it does bring a visual balance to the arrangement.
Be sure you bring different textures into the container planting and design. Add fine-, medium- and coarse-leaved plants. Use tall pieces that bring height for the focal point; shorter, mounding species en masse; and low-growing spiller plants to soften the edges of the container planting.
Lastly, use proportional sizes to match the container. For large containers, use larger plants; use smaller plants in small containers. The rule of thumb is that the tallest plant should not be taller than 1 to 2 times the height of the container.
Now is the fun part: picking the plants. Be sure that you use season-appropriate plants. For example, if you are creating a design for the summer, make sure you are using heat-tolerant, warm-season annuals and perennials.
Most trees and shrubs will be fine throughout the seasons, but be sure to use evergreen selections unless you plan to rotate them out with the seasons as you do with your annuals and perennials.
Here are a few suggestions of Louisiana Super Plants for each category for medium-sized containers.
Thriller plants: Suncredible yellow sunflower, Flamethrower coleus series, Fireworks pennisetum, Senorita Rosalita cleome, Intenz Classic celosia, Flutterby Tutti Frutti buddleia, Camelot foxglove series, Diamonds Blue delphinium, Jolt and Amazon dianthus series.
Filler plants: Beacon impatiens series, Babywing begonia series, Serena and Serenita Raspberry angelonia, Mesa gaillardia series, Butterfly and Lucky Star pentas series, Sorbet viola series, compact varieties in the Sunpatiens impatiens series, Kauai torenia series.
Spiller plants: Mini Vista Indigo and Vista Bubblegum in the Supertunia petunia series, Homestead Purple verbena, lemon sedum.
Heather Kirk-Ballard, Ph.D.
Consumer Horticulture Specialist
Heather Kirk-Ballard, Ph.D.
Consumer Horticulture Specialist
Enjoy the Garden,
Kathryn “Kiki” Fontenot, Ph.D.
Vegetable Gardening Specialist
Lawn |
Number of fertilizer applications/year |
Recommended months |
Bermudagrass |
3 |
March/April, June, August (optional September) |
Centipedegrass |
1 to 1.5 |
April and possibly June at ½ fertilizer rate |
St. Augustinegrass |
2 to 3 |
April, June, August |
Zoysia |
2 |
April and July |
Ron Strahan, Ph.D.
Weed Scientist and Turfgrass Specialist
Raj Singh, Ph.D.
Associate Professor
Director, Plant Diagnostic Center