Tips for Using Native Plants in Container Gardens
With many Southern California gardeners in a rush to transition landscapes designs to ones that require less water and maintenance, it may seem natural to evolve container gardens to meet the same criteria. Native plants come highly recommended as they are already adapted to local growing conditions.
Using native plants in container gardens is certainly doable, however, they can be a bit more difficult to care for than non-natives — even though a pot isn’t a natural environment for either option.
Given the likely extra effort, why would one opt for native plants in container gardens? To start, local birds, butterflies and other pollinators prefer them. And with their natural habitats shrinking so severely that migratory patterns and crop yields are suffering, this alone is a selling point for many gardeners.
Potted native plants do an excellent job of accenting or providing continuity of an already water-wise design through areas of hardscape such as large paver patios.
And, container gardens are portable which makes transporting them between homes doable for those on the move who would still like to participate in the native plant movement.
Understanding which native plants typically do well in containers along with their growing habits is the key to success.
Choose Plants with Longevity
Native plants tend to go dormant in the summer and gardeners often confuse this attribute with plant death. Dormancy is how the plants adapt to lack of summer rain in the wild. While this isn’t always noticeable on local hillsides or in flourishing gardens, container plantings meant to pack a punch may seem a bit lackluster during warmer months when you’ll probably utilize outdoor living spaces the most.
It might be preferable to rotate dormant containers out of view while the plants aren’t looking their best. Or, perhaps integrate succulents (try California native succulents like Dudleyas) into the native plant containers to provide year-round interest when the natives go dormant.
Therefore, selecting native plants that maintain beautiful color and texture that lasts for as long as possible during a season is important. A local nursery can advise regarding suitable options for your area if you are unsure which plants to pick.
Types of Containers
Container size is extremely important. Root systems of native plants usually require more soil than shallow-rooted succulents, for example. Square containers hold more soil than those with rounded bottoms that are of the same height and width. Or, opt for deep containers that are in more of a wine barrel shape (if not an actual wine barrel).
Try to choose one that will hold the plants for at least a few years at which point you can consider repotting it into a larger container or replanting it into the yard. Some experts advise buying as big of a container as you can carry because large containers allow gardeners more flexibility in regard to care. When the roots of some native plants are restricted, the plants are less likely to flower or mature fully. In fact, some will look like dwarf versions of their wild selves. An exception to the rule is that smaller perennials and native succulents do just fine in shallow pots.
Try to avoid dark plastic containers as the heat generated by them will rot roots. Go with breathable options like terra cotta. In reality, any container will do if you are mindful of sunlight, drainage and how quickly it tends to dry out.
Another requirement is that the pot has good drainage as native plants can’t handle soggy soil.
Soil sold at garden centers is not always appropriate for native plants because it tends to retain moisture, have too many fertilizers and break down quickly.
It is possible to make your own soil but taking a shovel to an existing part of the garden isn’t the solution. Intuitively, it makes sense to assume that native plants prefer soil from their native environment. However, a container garden provides an entirely different growing and drainage medium partially because small garden soil particle size leads to more water retention in containers… something that native plants do not like.
If it’s easier for you to buy potting mix, opt for a well-draining solution like cactus mix. If using native soil, add perlite until the soil has a light texture (about a 1:1 ratio is often recommended by experts).
Native Plants in Container Gardens May Need Repotting
You’ll know a pot has become too small when the plant’s leaves yellow and look lackluster. The pot will also dry out almost immediately because the plant’s root system has become so large.
However, it is possible to prune native plant root balls so that they can continue to thrive in the same pot. It involves trimming the plant into a dwarf shape and cutting away tangled exterior roots. Yerba Buena nursery has excellent directions online for how to do this. The best time of year to root prune is in the fall after the plant revives itself from dormancy and before active seasonal growth begins.
Maintenance and Care
The first thing to know is that native plants in container gardens (like most other plants) still require regular water. Allow the top inch or two to dry out before the next watering but make sure to never allow the container to run completely dry. If soil starts to compact, break it up gently (avoiding the roots) with a fork in order to ensure proper drainage.
Fertilize container gardens with native plants lightly in the spring. The roots can’t go in search of nutrients when in a pot so it’s up to you to provide them. Definitely do not fertilize during dormancy as it’s not wise to encourage growth during this time. A layer of compost is an excellent way to provide nutrients.
Keep the top of the container gardens mulched to absorb heat, prevent overly-rapid water evaporation and protect root crowns.
Pruning helps keep natives sized properly and looking attractive. Deadheading flowers will also encourage new blooms.
Next week, we’ll address the types of native plants to consider for coastal Southern California container gardens.
Which native plants do well in your container gardens?
Photo credits: Top, Flickr/zharkikh;