In The Garden
By Ralph Purkhiser, Purdue University Master Gardener
To become an AAS winner, a plant must stand up to trials in gardens across the United States and Canada. Professionals in the horticulture field evaluate plants that are grown in test gardens. The plants are also compared with similar plants that have been grown for a long time, many of which are themselves AAS winners. Sometimes, a particular plant may be outstanding in part of the country, but not the whole area. Regional awards may be given in such cases. Award winners are announced three times each year.
So far, only two edible selections have been awarded national AAS status in 2024. Broccoli Purple Magic, bred at Sakata Seed America, is described as an outstanding purple broccoli. It has tight, uniform heads and growers state it has great flavor. It stands up to stress and tolerates heat. The other winner is a bell pepper, Red Impact. Trial gardeners say it is very sweet, even when green. The peppers have thick walls. The sturdy, up-right plants produce a lot of peppers per plant. Red Impact was bred at Seminis Home Garden.
Six ornamental plants have been awarded national AAS status this year. Celosia Burning Embers is described as a tough plant, sporting bronze foliage with pink veins. The veins reflect the vibrant pink flower plums, which have good staying power. This Clover Seed Company introduction has been found to do well in hot, humid weather.
A geranium (pelargonium) described as low-maintenance has also been selected. Big EEZE Pink Batik has been found to keep the mottled pink flowers coming all season. It is also disease resistant. Drummen Orange produced this plant, which performs well in the ground or in containers.
Another versatile flowering plant is Impatiens interspecific Solarscape XL Pink Jewel. This Pan American Seed introduction starts well from seed. Vibrant pink, satiny blooms cover the mounding plants all summer. It can be used as a groundcover or as a filler plant in mixed contaitners.
If you want a great cutting flower, try Marigold Siam Gold from Thai Home Seeds. Large, fully-double, gold blooms are produced all summer on stems that do not need to be staked.
Petchoa En Viva Pink is a petunia relative and may be a good alternative to petunias in the garden and in containers. The plants have a mounding habit, and the flowers are bright, iridescent pink, with a yellow throat. One plant will fill the average hanging basket. It was submitted by Selecta One North America.
The final national selection is Verbena Sweetheart Kisses. Trial gardeners say this plant is easy to grow, whether in the ground, as a spiller in mixed containers or in a hanging basket. It produces blooms ranging from red to rose to pink, all blushed with white. Applewood Seed submitted this plant for trial.
There was one flower selected as a regional AAS winner for the Great Lakes Region. Petunia Sure Shot White also performed well in the west and northwest regions. It tolerates various weather conditions. Vibrant white blooms that are slightly scented will cover the plant all season. Ball Flora Plant submitted this plant. It will not be available as seed, but transplants will be available for growers.
Since these are new plants, they may be in short supply the first few years. The AAS website will list companies that will be offering these selections when they become available. Try something new with the assurance that professional gardeners have found them to be good plants for gardeners.
I got back from a trip to Indianapolis over the weekend and found hellebores in bloom at Sandhill Gardens. This is a signal that I have work to do. The foliage from last year needs to be cut, and as the new foliage come up, it makes it difficult to cut the old. It is time-consuming, but it is best to use some sharp scissors or pruners and cut one stem at a time. Trying to shear off clumps will almost certainly result in cutting off flowers and the foliage for this year. The good news is that this is the only real care the hellebores will need for the year, unless I decide to dig some and re-plant them. For this work, they will reward you with blooms that sometimes continue into July and nice foliage that adds a different texture to shade gardens. I have a couple of clumps that have variegated foliage, adding another form of interest.
In addition to the hellebores, winter aconite and some early crocuses are in bloom. These are tough flowers, and though very cold nights may cause them to wilt down, it will not kill them. Actually, the cooler weather will cause the blooms to last longer.
In a recent column, I gave instructions for winter sowing of seeds that need a cold treatment for stratification. Now, it is getting time to begin sowing seeds for tender plants. This must be done inside or in a hot bed, as these plants will not survive freezing temperatures. For vegetables, including tomatoes, peppers and eggplant, count back six weeks from our frost-free date to get the date to sow them. May 10 has traditionally been that day of being safe from freezing temperatures, but it has been a long time since we have had freezes that late. Also check the “days to germination” information on the seed packet. Some peppers are slow to germinate without bottom heat, so they may need to be sowed earlier. If you do not have a heat mat on which to set them, you may want to put the trays on top of your refrigerator until they have sprouted.
Caring for the seedlings inside can be a challenge. Started too early, they tend to get spindly before time to set them out. This is usually because they do not get enough light. If you want to grow good transplants, consider purchasing a grow light with a timer. Leave the light on for about 16 hours a day to give the plants the light they need to develop properly. If you have a sunny window, you may be able to grow without a grow light, but, just as the houseplants we discussed last week, they will need to be rotated frequently to keep them growing straight. The plants will grow toward the sun, which means they will grow toward the window. Keep an eye on them. They may need to be turned more than once a day!
I have had some questions concerning cold frames and hot beds, and how they are different. In general, they are the same on the surface, but a hot bed has a heat source. Usually, rotting manure in the bottom of the bed supplies heat. If you wish to build a hot bed, dig down about a foot. Fill that area with fresh manure. Horse manure is favored by many, as it gets hotter than some other manures. Then you need to build a frame around the bed, and fill the frame with compost or garden soil. The bed then must be covered with glass or clear plastic to hold that heat in. You have to watch the bed daily. If it is a sunny day, the temperature in a hot bed may get too hot, and you will need to open the top. The outside temperature will be the deciding factor on just how much to open the bed. Sometimes, it just needs to be open a few inches for ventilation, and other times it needs to be fully open. Just be sure to close the lid if freezing temperatures are predicted at night.
Crops like cabbage, lettuce, broccoli, cauliflower and related crops do quite well in a cold frame, but tomatoes, cucumbers, squash and other warm-season crops will need the heat of a hot bed if you wish to start the seeds early.
It is amazing how the additional light that February brings causes growth on houseplants. Plants in a sunny window have to be turned daily to keep them from growing toward the light. This lush new growth may also be a signal to cut some plants back to keep them compact and bushy. However, those cuttings may be put to use. When taking cuttings, be sure to use sharp tools. You may use a knife or scissors, or by-pass pruners. Do not use anvil pruners, as they may crush the stem. If there has been any disease in your plants, sterilize your tools with a mixture of rubbing alcohol and water or a weak bleach solution between cuts to prevent the spread of pathogens.
Stem tip cuttings include the terminal bud and at least two nodes. The nodes will become the source of the adventitious roots. Some plants will produce the roots easily, but others will benefit from a little help. Rooting hormones are available in powder and gel forms. When using the hormones, put some out into a small dish. Do not dip your plants into the bottle. When using the powder, dip the stem cutting in water and then dip it into the powder, making sure that the nodes get some powder. Use a dowel rod or other stick just larger than the stem to make a hole in the moistened potting mix. Insert the cutting in the hole, and press the mix in to touch the stem. Depending on the plant, roots will usually form in two to three weeks.
Some stem cuttings do not even need soil to form adventitious roots. Impatiens, tradescantia and other common houseplants will root if the stem is just placed in water. However, experts say that healthier roots form when starting them in a sterile potting mix.
You do not need to waste the rest of the stem once you have used the terminal bud. You can take other types of cuttings along the length of the stem. Take a leaf bud cutting by making two cuts—one just above a leaf node and another just below the node. Your cutting should include a leaf, a node and an axillary bud (see last week’s list of terms). Dip it in water and then touch it to the rooting hormone. Plant it in a moist potting mix.
Plants with thick stems may be propagated by a special type of stem cutting known as a cane cutting. Sometimes, this is a good way to rejuvenate a plant that has become a little leggy at the top or has just outgrown your house. A stem may be cut into sections about four inches long. You may either stand the stem vertically in the potting mix or lay it horizontally. If using the horizontal method, make sure that about half of the stem’s diameter is beneath the soil line. This method may result in several new plants, which may be divided after they begin to grow, or you may let them grow as a cluster.
Some plants will produce roots from the leaf petiole. Many people use this method for starting new begonias. Simply place the cut end of the petiole in the starting medium. The cut will form a scab, and a new bud will emerge. That bud will become a new plant. Just remove the original petiole when the new plant emerges.
Some plants, including many succulents, will grow new plants by simply placing the end of a leaf in the growing medium. When using succulent cuttings, it is usually best to allow them to scab over before planting them. I usually break off a leaf and wait three to five days before planting them.
Like all plants, starts from cuttings require moisture and light. Make sure the growing medium stays evenly moist, but not soggy. The plants also require humidity. For that reason, cuttings are often put in plastic tents to keep the humidity up. They also need bright, indirect light. With the advent of the LED grow lights, supplying good light inside is easy and relatively inexpensive.