Most people think of a garden as a space of cultivation in a backyard, along a fence or sidewalk or some other piece of land. But everyone can garden in a container regardless of where you live.

Advantages to container gardening:

• You can grow flowers, herbs, veggies, vines, even small shrubs;

---

---

• Excellent for beginners as well as advanced gardeners;

• Add a “garden” at any time including now;

---

---

• You can change looks, style, and fragrance easily and quickly.

Drawbacks to container gardening:

• Not all plants are suited for containers;

• Plants need more frequent watering and fertilization.

Choosing a container

Just about any container can be used as long as the container has never held toxic materials. 

Insuring drainage

Regardless of what container you select, it must be able to drain excess water. If it doesn’t have drainage holes, you need to either drill some in, or plant in a smaller container with drainage holes, then insert that container into the decorative container, setting it on bricks or rocks where water can drain.

Weight and size

If the container will be moved throughout the summer, plan to put it on a dollie as it will be much heavier with all the soil. Tall plants will need larger containers to avoid tipping over. A rule of thumb is that plants need a container that is at least as deep as the plant is high. In general, the smaller the pot, the more frequent the watering and fertilizing.  

Soil

Never use native soil because it usually has a high percentage of clay that easily compacts and reduces oxygen to the roots. Potting soil is a good choice.  

Water

Container gardens need more frequent watering than “in-ground” gardens because the exposed sides of the containers result in more evaporation. Even plastic containers may require daily or twice-daily watering as plants grow.

Do not allow containers to dry completely or fine roots will die. Salt buildup may occur, especially if you are using well water. By over-watering until about 10% of the water added drains out of the container, that reduces salt buildup.

Fertilizing

The rapid growth of many container plants quickly depletes the fertilizer in the soil. To provide the right amount of fertilizer, mix controlled-release fertilizer granules into the soil mix at planting. Diluted soluble fertilizers may be used with every watering, or at full strength on a weekly or every two-week basis, depending on the type of plants being grown.

Light

The light considerations for container gardening are the same as in landscape; choose the location that matches what the plants need. One good thing about containers is that if the location proves to be undesirable, you can move the container to a better location. Note that reflected sunlight off lightly colored buildings and paving may cause sun scald and result in more evaporation.

End of Season

It’s difficult to overwinter container plants outside, but you can move containers with perennials to an unheated location and water it monthly.  Many porous containers will crack if left outside, so they should be brought in as well. Finally, tempting though it is, never reuse potting soil from year to year as it may contain disease organisms. 

Gwen Swenson-Hale is a CSU Master Gardener from the class of 2021 and loves experimenting with flower containers.