Monday, June 7, 2010

Container Maintainer

Before we leave the topic of containers (for now) I want to cover a few aspects of maintenance. The most important rule for containers is: don’t let the planted container dry out. The amount of water  needed to prevent that varies dSw hydrang potepending on several factors. Plastic containers and glazed pots retain moisture better than clay, wood or wire baskets. Containers placed in the shade will require less frequent watering than those in the sun. Some plants are moisture lovers, others don’t like “wet feet”. The weather influences moisture in outside containers. The only way to know when your pots need to be watered is to check them daily. You can either feel the soil, or test the containers weight-or both. Experience will equip you to determine your own plants’ needs.

When you water, moisten the entire root area-add water until it is running out of the drainage holes. If the potting mix is allowed to dry out, it is very difficult to re-wet. If this happens you may need to soak the container. You can submerge the pot in a larger container to the soil level. If the pot is too large, try putting a saucer under it or even a plastic bag around the base and up the sides and run the hose into the container until water stands. This is the only time you are allowed to let your containers stand in water! You should not normally have outside containers sitting in anything that would impede natural drainage. When water fills the air spaces between the soil particles, the roots are unable to function normally and the plants may die. If you must use a saucer-perhaps you have a second floor balcony-half fill the saucer with gravel and place the pot on top.

Remember that container plants planted in soilless mix depend on you for nutrients. Your new plants are accustomed to being pampered. Nurseries feed every time they water to keep plants looking their best. You can feed your container plants with a low nitrogen liquid fertilizer-something like a 5-10-10 ratio. Many people use a slow release encapsulated fertilizer, such as Osmacote. This is a great product, but soil temperature must be above 50 degrees for it to work. Here in the cool PNW, you will get fewer months of extended use. Some soilless mixes have slow release fertilizer incorporated. Either way, even if you do use slow release fertilizer, experts recommend using liquid fertilizer every 3-4 weeks.

To keep your container looking its best throughout the seasons, you will occasionally need to groom your plants. This includes dead-heading, which simply means to remove fad11-04-07_1507ed flowers. Some plants will respond with fresh new growth if you cut them back after they bloom. Annuals need to be refreshed in this way at least once during the summer. You may need to prune trees and shrubs  in containers to improve their structure. In the fall, clean up and  remove dead leaves. There is a marvelous book on maintenance called The Well Tended Perennial Garden by Tracy Di Sabato-Aust. It describes in detail what to cut back, when and why.

If you plan to leave your containers in place outside over the winter, choose plants that are hardy two zones colder than where you live, since the roots of plants in containers may experience more extreme cold than those growing in your garden. In our area, near Seattle, most of us are USDA zone 8 based on the average annual minimum temperature range. If you are close to the water it moderates the temperatures and you can push the hardiness zone a bit higher-so know your microclimate. Many Seattle area gardeners enjoy pushing the envelope and they are successful until we have the occasional below zero winter which wipes out their subtropicals.

Sw pinknorgange If you select plants that are marginally hardy in your area, you may be able to overwinter them by placing in an unheated garage or shed in the fall. Check them a couple of times during the winter-water if necessary. After the chance of frost is over, bring the pots outside, clean them up and water thoroughly. I have been able to overwinter jasmine and fuchsias in this way.

Now is a great time to experiment with your containers!

No comments:

Post a Comment