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This week we're at Gwinnett Technical College. We'll learn about plant propagation, how to start plants from seed, from cuttings and division. These are great ways to start plants for your own garden or to pass them along to friends.

Starting plants from seed or cuttings is fun and actually easy, not difficult as many believe. First identify the nature of the plants you wish to propagate or multiply. Marigolds are annuals. Annuals have a short life, they are femoral. Femoral means they germinate, they grow and set seed in a few months. The best way to propagate this plant is by seed, that's mother natures way of propagating this plant. Also consider plant hardiness, the plants ability to withstand cold temperatures. A hardy plant will tolerate temperatures below 32 degrees. Dusty Miller and some Petunia varieties are hardy plants. A half hardy plant or half hardy annual will tolerate those temperatures but needs some protection. A tender annual will not accept temperatures that low, Marigolds and Begonias are examples.

In propagating plants start with cleanliness. Use a solution of 1 part bleach and 10 parts water. When working with flats used before - use this solution. Spray them or dip them in the solution. Afterwards wash them off to keep the chemical away from the plant. This process will protect the plant from fungus and bacteria.

When buying seeds from a garden center check to see when the seeds were collected. On every packet there is needed information, typically on the back. It will tell you the year of the seeds. If new, you don't need to worry about them losing viability. There is nothing wrong with using older seeds or seeds collected from your garden, they may just not be as uniform, probably resulting in a greater variation in size and height. A good way to save seeds is with a zip lock bag. Label them with a permanent marker and place them in a cool, dry, dark place - a refrigerator or a freezer is ideal. Germination of seeds is relatively easy. First select a container, a germination flat is best. They are typically 11 inches by 22 inches and 2-3 inches deep. They have tiny holes in the bottom that will allow excess water, excess moisture to drain through. We don't want to create a swamp and it has enough height to hold a good amount of soil. The soil mix should be very small particles or fine texture because that holds moisture well. The ideal soil mix has a lot of peat that, again, holds moisture. Pearlite is actually volcanic rock and is important because it holds air. Equal amounts of peat and volcanic rock are a good mix, both are relatively sterile, minimizing bacterial problems. Pour the mix into the germinating flat, until about half full. If filled to the top it would waste soil. Don't pack it, a good soil mix is already the right density. The soil should be as level as possible. Then completely and evenly saturate the soil with water, by doing this you shouldn't need to water again before the seeds germinate and start to grow. By watering before seeds are placed you won't need to worry about displacing seeds and washing them away. You can tell the soil is completely saturated if you notice water dripping from the bottom of the container. When placing the seeds there are several things to consider. Size is a consideration. If the seeds are very small, Begonias for example, have 2 million seeds per ounce, place those type seeds on the top of the soil surface almost like dust. Morning Glory seeds are large, so place them at a depth about 2 times their diameter. An easy way to do this is to take something like a plastic fork and make a little row in the soil, place them about 2 times their diameter deep and about 2 times their diameter apart from each seed. Once in the soil, temperature becomes a critical ingredient. Most bedding plants like to germinate at around 65 - 75 degrees. Lower temperatures will mean the germination process will take longer. A good place is on top of a refrigerator, it is probably a little warmer than the rest of the house. The key is to get the soil warm, more so than the air. Another concern is holding water, we don't want to re-water every day. One solution is to place a dome over the tray. A plastic cover from a garden center works well, it creates a bit of a terrarium like effect. Plastic wrap also works. Light is also an important ingredient. Some seeds need light to germinate, some need darkness. This varies by species, look up the individual plant to make the determination. If you want to limit the amount of light, and the temperature cover the plastic top with a newspaper. Remember 65-75 degrees is the ideal temperature. Once the seeds start to sprout they need sunlight. When left in the darkness too long they will become spindly or lanky. The seedling has just a small amount of energy stored, it will suffer if it has to look for light at an early stage. Therefore as soon as the seedlings sprout, which may be a week or two, get them to bright, indirect light. The best time to transplant the seedlings has to do with "true leaves," these are the third or fourth leaves that emerge. The first two are called cotyledons and they are not true leaves. When the third and fourth leaves emerge it's time to move the plant into it's final container or at least into a larger container where it can grow out. Select a container that will provide plenty of root space. Again, use a premium potting mix, one with good aeration, one that holds moisture well, however for this application one that is coarser than the germinating mix. Make sure the soil is completely saturated with water. Dr. Rick uses an 18-0-1. There are 18 individual pots in one flat, this works well if you're going to keep the plants in the container for a month or two. Saturate the soil with water. Place only one plant per cell, even if they are small. When moving try to touch only the leaves, avoid touching the stem or roots. Make a small hole in the potting mix and push the root system into the hole and potting mix. Tuck it in, making sure the seedling is about the same depth, possibly slightly deeper than before. Once the entire flat is planted, it needs to be hardened off. These plants were grown in greenhouse like conditions so they need to become acclimated to outside temperatures and conditions. An easy way to do this is for a week or so put the plants outside for an hour or so each day. Make sure the temperatures aren't particularly hot or cold. Once acclimated they can stay outside as long as temperatures don't drop below 32 degrees.

Pests can be a problem for our plants. Many pests are so small that we can't see them. The Spider Mite is an example. although very small it causes a lot of problems. One method of determining whether you have Spider Mites is to place a piece of paper underneath a leaf, then tap the leaf. The tiny mites will fall onto the paper and look like tiny specks of pepper, but they move. If present, a Mitacide is recommended. Mites are not insects, they can reproduce or complete their life cycle in as little as 3 to 7 days, they are extremely prolific. When Mites are severe you will see webs and thousands of Mites on your plants. Their mouth is like sandpaper, they tear into the leaf. This causes speckling or stippling on the top of the leaf. This causes not only aesthetic damage but they can kill the plant. They thrive in hot, dry conditions. Water is one way to control them, plenty of water on the leaves controls them.

Another way to start plants is through vegetative cuttings. A herbaceous plant is tender, succulent. The stems are full of water, there is no woody part to them. Take a cutting early in the day, when a lot of water is in the stem. They tend to root better at this time. The cutting should be 2-3 inches long. Use a sharp knife or scissors because they'll do less damage to the tissue. Remove the leaves from the stem that will go beneath the soil. You can actually remove a portion of the leaf, it will still be able to photosynthesize but not take too much room. The cuttings should not touch each other. Use a standard 6 inch pot - 6 inches across and 6 inches deep, fill it with a premium potting mix, one with pearlite and peat. Fill the container almost to the top with this mix, don't compress or push down on the soil because that removes air. Place the cutting gently in the mix. Make your cut below the node, where the leaves emerge. This tends to restrict fungus and bacteria from getting into the vascular system. Coleus is a good plant to start from cuttings. Place them around the outside of the container, leaning over the side of the container, this provides more space in the center of the container for more cuttings. Try to keep the leaves from touching, reducing the chance for disease. Once in place, use a fog nozzle to saturate the soil, trying to keep water from the leaves - again to reduce the chance for fungus and bacteria. With the container full, place a plastic bag and cover the entire pot. If needed put a piece of bamboo in the container to hold the bag up. This creates terrarium like conditions with high humidity, keeping the cuttings from transpiring (too much water from leaving the leaf surface). This creates a situation where there is almost 100% humidity, they'll root easily and we'll be able to gingerly take them out and have new plants.

Division is another way to start a new plant. This entails taking an entire part of a plant, removing it and starting a new one. This is an asexual approach, which unlike seed production requires two different parents to produce seed. In this case we're taking a clone or section of the parent plant. Irises work well with this approach. The best time to propagate Irises is right after they bloom. You'll need a sharp knife, possibly a saw. Remove the above ground and below ground parts of the plant. What remains is the rhizome, the underground stem. This is where the plant stores its food and energy. It is a large white part of the plant just below the soil surface. Do make sure it has healthy white roots. Cut this into 1-8 different fans depending on the size of the rhizome. Look for young, plump material, then make your cut. Make sure it fits into the container you've planned. Don't place it too deep because the crown could be damaged if planted too deeply. Use a premium potting soil and make sure the soil is moist. This shocks or stresses the plant, it will take a week or so for the plant to recover. Dr. Rick likes to start them in pots so he can offer greater care.

Another way to start plants involves taking a leaf cutting from, for example, a Dragon Wing Begonia. Remove just one leaf from the plant, this allows a large number of cuttings. A large leaf with large veins is needed. Cut through the vein in about two different places. Set it on the soil so that the leaf touches the soil surface. Use something like a paper clip, open it up fully, then using the clip press the leaf to the soil, making sure good contact has been made between the soil and the leaf. You might want to add some soil to the top of the leaf. Keep this moist, Dr. Rick uses a dome over the soil and leaf to keep it moist. After several weeks roots will form and you will have the beginning of a new Begonia.

Link: Barnsley Gardens

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