Choosing a Clay or Plastic Pot for Plants (typeofpots)
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Choosing Clay or Plastic Pots
by Don Janssen, UNL Extension Educator
Many gardeners have their own preferences regarding the choice of clay or plastic pots for their plants. If you do not have a firm opinion either way this article will detail some advantages and disadvantages of both types.
Terra-cotta (unglazed clay) pots are made of a particular soil and fired in kilns during the manufacturing process. The rusty brown color of clay is harmonious with every flower and foliage color.
Clay pots provide a healthy environment for most plants. The porosity of clay allows air and moisture to penetrate the sides of the pot. This moisture and air is utilized by the fine roots located at the edge of the soil ball. Clay pots also act like a wick to remove excess moisture from the potting soil. This can be looked at as both an advantage and a disadvantage depending upon your watering habits.
Gardeners with a heavy hand at watering tend to over-water; their plants will probably benefit from clay. Other gardeners who wait for the wilting signal from their plants are better off with plastic. Plants which demand a well-drained, dry soil like cacti also prefer clay pots.
Outdoor usage of clay also has advantages. Clay pots have thick walls that protect plant roots from rapid changes in temperature which can be destructive. They also have a fair amount of weight and do not blow over as easily as some plastic pots. Clay does have the disadvantage of drying quickly. This can be a problem for moisture loving plants such as ferns or when attempting to germinate seeds.
Clay also has the tendency to form a white crusty layer on the outside of the pot. This is formed when mineral salts dissolved in the water are wicked from the potting medium into and through the pot wall. Some find this layer attractive, most gardeners find it unsightly. The salt deposits can be scrubbed off if their appearance offends. A final disadvantage, clay is easily broken.
Plastic pots are lightweight, strong and flexible. They are available in every color of the rainbow to coordinate with interior and exterior decor. Plastic does not have the wicking action that clay has making them an excellent choice for moisture-loving plants or for those gardeners who water infrequently.
Plastic pots are made of inert materials and are considered safe for growing plants. Many are made of recyclable plastic so disposal is environmentally friendly when the pot is no longer usable (unglazed clay pots are fully recyclable as well). Plastic pots generally have thinner walls than their clay counterparts offering roots little if any insulation from temperature change. Black plastic can actually act as a solar collector, heating up the potting medium to plant damaging levels.
If plants in dark colored plastic containers wilt quickly, check to make sure the plants are well watered then move them to a shadier location where heat build-up should not be a problem. Sunlight can be hard on plastic causing fading and brittleness. Many plastic pots intended for outdoor use are treated with ultraviolet light inhibitors to reduce fading and maintain flexibility thus increasing the life-span of the pot.
Whether it be plastic or clay, make sure the pot you select has drainage holes in the bottom to prevent over-watering.
University of Nebraska-Lincoln Extension in Lancaster County is your on-line yard and garden educational resource. The information on this Web site is valid for residents of southeastern Nebraska. It may or may not apply in your area. If you live outside southeastern Nebraska, visit your local Extension office
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Clay Pots vs. Plastic Pots – Should You Use Clay Pots Or Plastic Pots
Choice of containers is largely a matter of personal taste, but if you’re committed to old-fashioned clay, you might want to try plastic containers instead of clay. Plastic containers have evolved over the last couple of decades and offer a number of advantages, at least for Mary, over old-fashioned clay pots. As a lifelong plant freak, Bonnie has experience with containers for plants too.
While many of our new plants will come to us in plastic containers from a nursery or big box store, should you keep them in those pots? There is more than aesthetics at stake here. The health of your plant could be in jeopardy if you keep it in that convenient plastic container. Let’s see which side of the question you are on and if either of our writers can change your mind.
Pros of Clay Pots vs. Plastic Containers
(Bonnie’s viewpoint) One of my favorite plant groups are cacti and succulents. Their amazing variety of form, adaptability, and ease of care make them a no brainer for houseplant enthusiasts. The type of container you keep these in, however, is a subject up for debate. Are there benefits of clay pots vs. plastic? I have a very definite opinion and several reasons why you should use clay over plastic.
Plastic isn’t very eco-friendly. Plastic containers may be lighter and readily available, but they aren’t environmentally friendly. Conversely, clay or natural terra cotta containers are made from a special soil that will eventually break back down into its original components should the pot break. Those pot shards are also excellent used in the bottom of larger pots to increase drainage.
Among the problems with plastic containers are their contribution to litter and health problems in humans and animals. Many municipalities do not offer recycling of plastics and those used items just go into the landfill where they release petrochemicals and other bi-products of their construction. We are literally drowning in plastic items that don’t break down easily and when they eventually do, only release tiny particulates that clog our soil and oceans. Just look at the plastic bag and straw debates already raging and see if using a plastic container fits into our ecological goals.
Clay is more adaptable. While not a long-term solution, when I do purchase plants, I try to buy ones that come in compostable pots. This doesn’t work to keep plants for the duration and are only meant for quick transplant into the garden. One of the many pros of clay pots is their reusability but there are other reasons to use this natural material to house our plants. You can use glazed pots, but I prefer to avoid the chemicals in the coating and use unglazed containers, which help remove excess moisture by evaporation.
Plastic remains wet. The plastic has no porosity and plants are prone to staying too wet. Clay allows movement of air and water. This can mean more watering in certain plant species but is useful to prevent root rot and soil fungus. This action helps prevent certain insect pests that like moisture too. They’re perfect for cacti and succulents because the soil will dry quicker and the walls are thick and protective.
Clay pots care heavier. The pros of clay pots over plastic include their durability. Useful in households with active children or pets because they are heavier and harder to tip over. Their weight makes them good for hardening off seedlings outdoors where wind might topple lightweight plastic. Sunlight also causes plastic to become brittle over time.
Clay is attractive with lots of variety. Other benefits of clay over plastic are that they develop a lovely patina over time. They’re relatively inexpensive and come in a variety of sizes.
Advantages of Plastic Pots Instead of Clay
(Mary’s viewpoint) Yes, there are many benefits to clay but I feel the pros of plastic pots are far better alternatives. And these are my reasons why.
Variety. One of the advantages of plastic pots is that they, too, are available in a huge variety of shapes, sizes, colors, and textures, including whimsical designs. But unlike terra cotta pots, you can easily select plastic containers to harmonize with your décor, or to set off the color of your home’s exterior.
Water retention. Yes, plastic pots hold more water than clay, but this makes them an ideal choice for plants that thrive in moist soil, or if you tend to forget to water. One of the downsides to clay pots is that clay is porous. Clay pots wick water and potting mix dries out faster which means you need to water plants more.
Durability. Newer plastic pots are tough, durable, and virtually unbreakable. A major downside to clay is that the pots are easily cracked or chipped, which rarely occurs with plastic pots. Clay pots are likely to break during freezing weather, but plastic pots are more flexible and are usually able to withstand repeated freeze/thaw cycles all winter long.
Lightweight. Do you like to move your plants from place to place? The weight of the containers is one of the downsides to clay. Plastic is lighter and even larger pots can be easily relocated.
Price. The pros of plastic pots include the reasonable price. Clay pots are often hugely expensive, but high-quality plastic pots can usually save you a few dollars. If you want to change pots from time to time, using plastic pots instead of clay won’t break the bank.
Recyclability. As gardeners, we are concerned about our impact on the environment, especially single-use plastic, but today’s higher-quality plastic pots are often recyclable. Look at the bottom of the pot for information about recyclability. Be sure the pot is clean before you take it to the recycling center.
Clay Over Plastic or the Other Way Around?
Plastic and clay pots each have certain advantages and disadvantages, but if you think plastic pots are flimsy or tacky, it’s time to take a second look. Newer, higher grade plastic pots rival clay in terms of variety, durability, and appearance. But for some people, like Bonnie, who’s a clay pot girl, their view is different.
The versatility, availability, economical and reusable nature of clay pots appeal to those with tree hugging sentiments and somewhat tight with a dollar. Bonnie does add, “I do save my plastic pots when I purchase plants that come in such containers and use them until they crack and crumble. But when it comes to transplanting a new specimen or propagating from one that is ready to have babies, I reach for my clay pots. Nothing looks as natural and appealing to me as a nicely aged clay pot with a tumble of new plants, both indoors and out.”
Clay Pots vs. Plastic Pots – Should You Use Clay Pots Or Plastic Pots Choice of containers is largely a matter of personal taste, but if you’re committed to old-fashioned clay, you might want to