Pamela's book "Instant Container Gardens" and the design of all the new side planting containers is based on Ten Years of Research, experimenting with over 10,000 Plants! Pamela is also happy to answer any questions or concerns from Garden Centers. Please e-mail her for a personal reply. In Pamela's own words about her seminars and demonstrations: "Whenever anyone poses an objection to me, I immediately say 'Great Question! I was hoping you would bring that up!' and follow with the technical data they are asking about. I had many failures along the way and understand people's concerns. The subjects they pose are legitimate worries for people, particularly experienced horticultural people!"
1. Sizing of holes
We tried holes from 1" to 2.5" in diameter to discover the best possible size. The 1.7" size is far and above the best choice for 3" to 4.5" root balls. Smaller sizes tear up the larger root balls and larger ones allow the root balls to fall out.
2. Corner slits around holes
We tried slits from .75" to 2". The four x 1" slits are perfect. Smaller slits didn't allow passage of the root balls and larger slits bulged after the plants were placed.
3. Expect some potting mix to escape
After you place the root balls inside the container, you will see a small open space. At first, we put loose coco-fiber in these spaces so that no soil could escape. Then we tried planting without the loose coco-fiber and the results were the same! We planted hundreds of these containers with fabulous results! Firm the potting mix slightly with your hand (in the area of the hole outside the container) after planting and expect a small amount of mix to escape, but nothing significant. The roots grow so quickly in these containers that the soil stabilizes quickly.
If the containers are placed over hardscape (sidewalk, decks, etc.), expect to sweep up occasionally just like you would if your container gardens dropped flowers or leaves.
4. Not all plants survive side planting
Some plants like side planting and some don't. We tested thousands of plants to find out which did and which didn't. All the fuchsias died quickly, as did the marigolds. Coleus, begonias and impatiens thrived. Check the planting label on each pot, or Pamela Crawford's Instant Container Gardens" book for this information before planting.
5. Proper post mounting
We tested many different mechanisms for keeping the basket on the post. The large baskets are heavy and need to be mounted properly. We first tried smaller disks and the pots fell off. The 9" disk is perfect. Our containers went through three direct hits from hurricanes and stood tall on their post mounts!
6. Watering Basics (See Instant Container Gardens" for detailed watering instructions)
Our initial trials of the instant containers were in the fall, winter and spring in southeast Florida and in the summer in New Hampshire. The temperatures seldom hit more than 90 degrees in these areas during our trial seasons. Most of the containers were watered by drip irrigation or ground sprinklers. When they were first planted, we watered them about every 3 days in sun, every 5 days in shade. When they were fully grown, we watered them about every other day in sun and every 3 to 4 days in shade.
Our Georgia (near Atlanta) trials followed. These offered much more of a challenge, because we were determined to find out if these containers were a viable option in hotter conditions, like a Georgia summer. Since we wanted to know exactly how many times these containers would need water, we used no automatic methods at all the containers were hand-watered.
When the June temperatures hit 97 degrees, we were quite concerned that the porous coco-fiber sides of the containers would inhibit the water-holding capacity of the container we even had visions of watering four or five times a day to keep the container alive! Luckily, that was not the case. We watered them, at the most, once a day if they were planted in sun. The shade containers NEVER needed watering more than once every three days.
In areas that are hotter than Atlanta (e.g. Houston), July and August may be challenging months for almost any container planted in full sun especially if it is in a windy situation, or against a white wall. But these super-hot areas have long growing seasons, so spring and fall would be easier times for container gardening in sun.