The first step of a successful landscape is a good design. A key element of a good landscape design is the proper setting of shrubs in the landscape. Each plant has its own requirements for the amount of sun, soil type, drainage, and cold winter wind exposure. Each shrub should be planted with its mature height and size in mind, not what it looks like in its pot at the nursery. The successful landscape first starts with an excellent plan. It is also cost effective to do it correctly the first time. A North Metro Atlanta plant list is provided here. The plants are grouped by size and sun exposure requirements.
Shrub Installation
Once a plant is selected based on its full growth size, its sun and wind exposure, and its soil condition and drainage, it is time to plant. The best time for planting shrubs is in the fall, followed by the winter, and lastly, spring. Planting plants in the heat of the summer requires experience and excellent care. Most soil in North Metro Atlanta is heavy red clay. It sticks together like glue and does not drain well. The clay can become as hard as rock, and sometimes requires a pick axe and a great deal of strength to dig an adequate size planting hole. This clay not only drains poorly, but prevents the roots from spreading to create a healthy plant that can soak up enough water and nutrients. A hole in such hard clay can form an outdoor bathtub, filling with water during a heavy rain and drowning the plant. A healthy shrub has a well developed root system which requires water, oxygen, and nutrients. Proper installation, watering, pruning, and fertilization make for a healthy plant.
- Dig the hole at least twice as wide as the plant’s root ball. The harder the soil, the wider the hole should be.
- Amend the soil. With the soil sitting in a pile from your hole excavation, pour on soil conditioner, mushroom compost, or cow manure onto the pile and mix it with a shovel. After properly positioning the prepared plant, use this mixture when refilling the hole.
- Prepare the plant’s root ball. For container grown plants, the dirt and roots at the edge of the container ball need to be loosened to prevent the plant from becoming root bound. The edge of the roots and soil should be loose enough to allow the roots to spread into the surrounding soil. If this is not done, the roots can become trapped in a hardened root ball.
- For ball and burlap plants do not remove the burlap. After the plant is planted, open the burlap at the top of the plant and pull the burlap away from the trunk. Leaving the burlap wrapped at the base may suffocate the plant. Removing the burlap before planting may result in the dirt in the root ball separating and breaking the root. This kind of root damage may not be readily visible, but it can kill the plant. For this reason the plant should be carried by the root ball and not by the plant or tree trunk. The weight of the dirt may cause the plant roots to break inside the ball, thus killing the plant.
- Don’t plant the plant to deep. Adding dirt to the top of the plants existing soil may suffocate the plant’s crown and kill the plant. Often times, it is better to leave the plant an inch or two above the surface and slope the dirt up to the plant’s root ball. This can improve drainage, and insures that the plant crown is not buried, which is a fatal mistake.
- Water plants thoroughly after installation. Air pockets in the dirt around the root ball may result in dried out roots. Adding root starter to the water can be essential for larger shrubs and trees, and will benefit plants of all sizes. Newly installed materials should be watered daily for two weeks. Plants installed in the spring, when flowers and new leaves are emerging, need extra water. Plants planted in the summer need extra water due to extreme evaporation loss. Plants planted in hot, dry soils can suck the water right out of a root ball and kill the plant quickly if not watered immediately after planting. A few hours in 95 degree heat can cause severe plant damage.
- Fertilize plants at the time of installation with a small handful of 10-10-10 mixed in with the soil. Time release fertilizer pellets may be used, touching the root ball a few inches below the soil level, to provide continuous feeding. For the first three years, fertilize in early spring and late summer with 12-6-6 or 21-3-12, timed release.
Shrub Fertilization
Shrubs can be fertilized with liquid, granule, and time release granule fertilizers. Liquid fertilizers provide quick impact. Time release fertilizers are more expensive, but provide nutrients for up to nine months. What is important to know is when to fertilize, how to fertilize, and at what strength.
Over fertilization can badly burn or kill a plant. Fertilizer should be spread around the plant. It should never be dumped on the plants center, or crown. Flowering shrubs should not be fertilized prior to or during the flowers bloom period. This may curtail or eliminate the flower’s bloom.
What fertilizer should you use? Fertilizer content is described in three numbers like 13-13-13 or 5-10-5. These numbers tell you the amounts of the three primary nutrients in the fertilizer. The first number is the percentage of nitrogen (N). Nitrogen helps the plant grow more leaves and branches, while at the same time giving the leaves a healthy glow. The second number is the percentage of Phosphorous (P). Phosphorous encourages strong root formation and good flowering. To produce flowers and fall berries, use a type of product with a higher phosphorous ratio like 5-10-5 or 6-12-12. The third number is for potassium or potash. Potassium promotes hardiness, disease resistance, and plant strength.
Fertilization is most important when transplanting for plant establishment and during its first year. We like a granular time release fertilizer called Osmocote. It is great on pansies and other annuals, and just about everything else. Some plant requirements for fertilizer are greater than others. A few plants react negatively to fertilization, but for most it is very beneficial.
A good fertilization schedule begins in April for most shrubs, except spring flowering shrubs. Begin spring flowering shrubs fertilization after flowering. Fertilization in February, for example, may push new growth which could be killed by March or early April freezes. Refertilize in late summer. Fertilizing in the heat of mid summer may overstress a shrub. This policy excludes annuals and perennials.
Plants such as azaleas, rhododendrons, and gardenias like Miracid fertilizer. Annuals and perennials should be fertilized every 4 to 6 weeks during their growing season. Pansies like Osmocote fertilizer, or fertilizer with “Nitrate Nitrogen”, which can be absorbed during cooler weather. Yellowing leaves on a plant may indicate a nutrient deficiency. An application of liquid fertilizer is the quickest way to get the plants the nutrients it needs.
Plant absorption of nutrients is effected by soil PH. Knowing the proper PH for a plant is important. Changing a soils PH to the plants needed PH is very beneficial. However, changing the PH in the wrong direction can be fatal. A soil test done by your county extension service will guide you in the right direction. It is best not to guess.
