Designing, planting, and maintaining a large container garden can be a challenge both physically and aesthetically, but here are five no-nonsense tips to ease the task.
01 of 05
Creating a container garden begins with selecting the right planting medium to fill your container
Use a good quality soilless potting mix to fill large containers because it is lightweight and drains well; adequate drainage is crucial for successful container gardening.
When water does not drain from a container, water fills the soil air pores, and when that happens, roots can't breathe or exchange gases. The plants will eventually die from lack of oxygen.
If you are creating a container garden in colder climates such as USDA Zones 5 and lower, do not use soilless potting mix that contains moisture retention granules because they will freeze.
A possible disadvantage to using a soilless potting mix is that it is very lightweight and dries out quickly. However, adding packaged pasteurized potting soil to the soilless mix at a ratio of one part soil to three parts soilless mix will provide more substance and better water retention. Though helpful, adding potting soil is not required.
Never fill a container with garden soil. Garden soil is too dense and heavy, compacts easily, does not drain well, and it doesn't provide proper aeration. Garden soil might contain pests that can contaminate your container with unwanted elements such as fungi, soil-borne adult insects and larva, and weed seeds.
The advantage to using lightweight soilless potting mix can be significant, particularly if you ever have to move the container or are placing it onto a deck or balcony where weight can be an issue. A large container filled with damp soil and plants can become very heavy. Generally, the more soil a container has, the more it will retain water, and that can be a good thing. However, a large container requires quite a lot of to moisten the soil all the way to the bottom of the container.
When you are filling and planting a large container with soil, it's best to do so in its final location so that you don't have to move it once you are finished planting.
Never add layers of gravel, rock, or stone to the bottom of a container. Contrary to popular belief, doing so does not improve drainage and might contribute to the soil being too wet.
02 of 05
Choose Your Plants Carefully
While plant selection is important for any container, its essential for large containers. Small and compact plants can be easily overwhelmed in a large container. It can be a challenge to choose plants that complement each other and contribute interest and balance to your container design. Particularly in large containers, the container design principle of using "thriller, filler, and spiller" plants can provide proper structure and balance.
Thrillers are tall plants that add drama and a vertical element to a container. Think of a thriller as the star of the container. If your container is large enough, you might want to add more than one thriller. Examples of thrillers are tall annuals and perennials, ornamental grasses, and perhaps small trees and shrubs. Using trees, shrubs, or large perennials that can survive the winter in your area provides the added advantage of being a year-round container.
While it's common to use several different fillers and spillers in mixed containers, don't hesitate to use only a single type plant in a container. For containers that are wider than they are tall, one low-growing ground cover like golden creeping jenny or a low-growing succulent can look stylish and interesting, particularly when planted in a spectacular container.
03 of 05
Give Your Plants a Good Start with Fertilizer
It is better to add your own organic, slow release fertilizer to your soilless potting mix than it is to purchase potting soil that already contains fertilizer. To do so, fill a wheelbarrow or other large container with your potting soil mix, and use your hands or a garden tool to evenly blend the slow-release fertilizer throughout the soil before you add it to your container. When you fill your container, fertilizer will be available to the plant's root systems as the roots grow deeper and deeper into the soil
04 of 05
Besides locating your container where it receives the appropriate amount of sunlight for the plants you've selected, follow these horticultural practices to keep your containers looking healthy and beautiful:
1. Keep up with deadheading. While some flowering plants don't require deadheading, many do require deadheading. It's beneficial to remove faded flowers to keep the flowering plants in your containers looking neat, to encourage more blooms, and to discourage the plants from going to seed.
3. Fertilize containers regularly throughout the growing season. Many large plants are heavy feeders, so use a diluted liquid fertilizer every other week to keep them healthy and well fed. With every watering, nutrients leech from containers so it's important to maintain a regular feeding schedule.
4. Make sure your plants are receiving enough water. Especially with large plants, foliage can act as an umbrella, and light rain or water from a hose can be shed before it has a chance to reach the soil. You'll know that you've watered well when you see water seeping out of the drainage hole at the bottom of the container. If you don't see water draining from the container, you have not watered enough.Continue to 5 of 5 below.
05 of 05
Finding Beautiful Large Containers
A lovely, large container can be a piece of art and a focal point of your yard, deck, or garden. Many big beautiful containers also have big beautiful price tags.
The only requirement for a container is that it must have drainage holes at the bottom, otherwise water cannot drain. Containers that are intended for outdoor use come with pre-made drainage holes. You might have to drill drainage holes in plastic containers that can be used either indoors or outdoors.
If weight is a concern, consider purchasing a container made from fiberglass. They can be equally as fancy and beautiful as a hand-thrown terra cotta container.
You don't have to spend a lot of money to get a fabulous container. Very often, large containers made from terra cotta, fiberglass, wood, and ceramic are sold at local independent nurseries and garden centers, home improvement stores, home design stores, flea markets, thrift stores and garage sales.