Thank you for reaching out to OSU Extension! These are great questions as we head into the next season.

Fall fertilization

Fertilization of your shrubs, garden and plants in the fall leads to a beautiful, healthy spring garden — it’s the ideal time for feeding if you do it right. When temperatures drop to 40 degrees or lower, plants are stimulated to produce higher concentrations of the materials they need to resist freezing. Fertilizing in the fall helps plants be hardier when the temperatures drop.

We also recommend applying fertilizer in the late fall, toward the end of October or early November. This application will catalyze one last frenzy of root growth and really give your plants some staying power through the cold months.

Here are some helpful resources:

• Fertilizing Garden Plants, OSU Extension Service Metro-area Master Gardener Newsletter
• Know what your plants need before fertilizing, OSU Extension news story

Fall watering

Frequency is largely a matter of preference. For most of the irrigation season, lawns will need to be irrigated from 1 to 3 times per week if you want an attractive lawn. Perhaps the best way to gauge frequency is to watch the lawn. If you are irrigating once per week and the lawn turning brown between waterings, you should irrigate more often. As fall approaches, try to reduce the amount and frequency of irrigation.

The following OSU Extension publications provide more detailed information:

• Turfgrass maintenance calendar for Central Oregon
• Efficient Lawn Irrigation in the Intermountain West
• Gardening in Central Oregon's climate

Sprinkler systems are winterized in the Central Oregon area generally around late September or the beginning of October.