Container Gardens 101 – The Pots
Gardeners all over the country grow plants in pots. With the trend increasing for small-space gardening, it’s only natural to look at pots as part of the solution. Choosing the right types of desert garden pots will lead you to success sooner as the pots are the foundation of your garden.
I am going to start with the fundamentals. Even my most advanced gardeners who have followed my book, emails and taken my classes always say they learned something more. When planting in containers, there is a particular method for plant survival. First, I will discuss how to choose pots that enhance your patio and are the best to support your plants.
Ideally, pots should be at least 18″, measuring the interior diameter. Living in the desert, this is the smallest size I recommend for pots in the sun. I’d prefer 20 inches or more.
The reason we start at this size is that to build up moist insulation around the root systems, we need that volume of soil in a pot. Of course, gardeners around the country use smaller pots, and there is a place for them in our desert gardens. But to plant combination plantings, large plants, trees or shrubs, or even a bouquet of annuals, the bigger, the better.
>>Marylee’s Rule #1 Choose the biggest pot that fills the space you want to put it in; that you are willing to spend your money on.
Plants are accustomed to being planted in the ground where they can spread their roots out as they need. They reach for the water and a stable system that will support their above-ground structure.
Too small of a pot will restrict root space. Therefore, we want to give the roots as much room as possible so they can support the upper structure of the plant to help it thrive.
Desert Heat Demands More
Besides root space, a large volume of soil will help insulate the heat when the pot is placed in full sun. This is particularly important during the summer heat, which can range from March to November, depending on if you live in the low or mid desert regions. High desert summers are shorter by a month or more on both ends.
Additionally, the large pot’s soil volume will be better equipped to retain consistent moisture. A small or medium pot dries out too fast and you risk soil and roots that are alternately wet and dry. The lack of regular water stresses the plant and deteriorates the planting mix so that it cannot be re-hydrated. These conditions can lead to plant failure.
>>Marylee’s Rule #2 Maintain a consistent watering schedule for your pots.
Pot Size by Interior Diameter: (According to Marylee)
• Medium 16″-18″
• Large 20″-22″
• Extra-large 24″-26″
• Jumbo 28″ and up
Therefore, anything less than 16″ is a small pot in my list of definitions.
Why So Big?
I already spoke about the room to grow in the paragraph above. However, there are other reasons for choosing larger pots.
Soil, Food, and Water
Plants need a home and with it, a supply of food and water. Their home is the pot filled with soil, and if there is not enough, there cannot be enough nutrients or water available. In hot and dry weather with days filled with intense sunshine, a small pot is going to need watering two to three times a day. It is much healthier for the plant to have a stable moist environment rather than the ups and downs of dry and wet conditions.
Pots around your home should be in proportion to where you place them. You know how to choose an end table for your sofa. In the same way, think about the size of a pot adjacent to an outdoor sitting area, the patio corner, or by posts supporting the ramada. Out in the yard, the distance will diminish the size of the container.
Larger plants look out of balance in a small pot. Additionally, as I discussed before, a smaller size pot would not be able to support a large plant, and you will most likely find it toppling in the wind.
Desert Garden Pots – Materials
You can use almost anything as a planting container. If you are planning to use deeply rooted plants, you need to make sure your pot is as tall as it is wide, but for shorter roots, many gardeners will plant in wheelbarrows, bed frames and low bowls.
Full sun pots should be containers that have thick walls. This helps to insulate the soil and roots. My favorite are pots made of glazed clay or ceramic because I believe they will outlive us for generations to come if they are not exposed to freezing temperatures when wet.
These high-fired glazed pots will have thick walls and by being high-fired, will keep in the moisture while not getting the salt or calcium build up on the outside of the pots.
Mexican clay pots are very porous and dry out more quickly. They will wear out in a few years from all the moisture and in the meantime, build up unseemly white residue from the desert’s high-pH water.
You want to be careful if you are in a hot area and not choose metal pots. The metal will conduct the heat right into the soil and risk burning the roots. However, I have successfully used sheet insulation inside the sunny side of a metal container.
I am biased against plastic pots because I believe our homes are worth more than a plastic container.
If you prefer these pots that are easy to move, it has to be a heavy-duty plastic, or preferably the light-weight pots made from resin or polyethylene but only if they have a thicker wall than plastic containers.
Get the skinny on pots
That word skinny might make or break your potting experience!
A skinny pot is a narrow pot far taller than wide. It can be a cylinder or what I refer to as a tall-square pot. These pots are beautiful in their simplicity and lend a strong vertical element to your design. They can stand alone or be grouped with two other containers. We do, however, need to use them smartly as there are some risks involved.
Primary Concerns of Using Tall Skinny Pots in Your Desert Container Garden
1. The Tipping Factor – Strong winds or large nosy creatures such as deer and javelina (wild pigs) can easily tip over tall skinny pots. Place them in corners or other areas close to the house, near the front door and areas where you know a wind tunnel will be least likely to jeopardize the pot.
To keep critters away from your pots, it’s nice to have a wall or fence with a gate.
Also, planting a tall plant in a tall, skinny pot increases the tipping factor as the pot may become top-heavy. Consider planting short to medium height plants in this type of pot.
2. Root Room – Tall, skinny pots measuring 8 – 14″ provide vertical root space but not substantial width. Shrubs and trees need a lot of space to develop their roots to sustain their growth and health. In this shaped pot, the roots will dive to the bottom of the pot. The other dangerous type plant is one with nodules on the roots – such as Boston or Asparagus Ferns. These plants quickly become root-bound and hence comes the problem.
Most plants will outgrow tall, skinny pots. They will either need to have their roots trimmed or planted in a larger pot. The problem comes with trying to get the enormous root ball out of the container. A saw is often needed – which… will risk the plant or the pot!
My advice? Don’t plant any of these plants, i.e., shrubs, trees and ferns in tall skinny pots.
While we’re at it, let’s talk about a similar problem with urn-shaped pots. With the opening of the pot narrower than the pot’s center circumference. You will never be able to pull a giant root ball out of the pot. Again, you end up trying to saw the root ball or breaking the pot… if the overgrown roots don’t break it first, destroying the container.
So tall skinny pots and urns have their place in your garden, try planting small rooted plants or annuals in them.
The Perfect Desert Garden Pot for Large Plants
All that said about tall, skinny or urn-shaped pots, a V or U-shaped pot will provide you with years of comfortable growing room for annuals, perennials, shrubs and trees as long as it is large enough to support the type plant you’ve chosen. Please remember my urging to use pots over 20″ for shrubs and over 24″ for trees. The bigger, the better.
A final bit of advice
Two Signs that it is time to prune the roots
1. If you water the plant and the water goes right through the pot and drains out immediately.
2. If your plant is droopy in the afternoon and you water it deeply. Check on it the next morning and if it is still drooping, it most likely you will want to trim the roots early in the spring.
There’s much more to be learned about choosing pots for your desert home and Marylee can help.
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