What to Do in Your Boise Garden Before the First Freeze
October 7, 2026 | News
The first freeze is coming, but that doesn’t mean gardening season is over. In fact, fall is one of the most important times to prepare your Boise garden for winter and set yourself up for a healthier, more beautiful landscape next spring.
Boise’s changing fall temperatures can make it tricky to know exactly when to wrap up the garden. One day can feel like summer, and the next can bring a chilly night. Before temperatures drop, there are a few important things to check off your list.
Here’s what Boise and Treasure Valley gardeners should do before the first freeze.
1. Keep Planting Trees and Shrubs
Don’t put your shovel away just yet!
Fall is a great time to plant trees and shrubs in Boise. Cooler temperatures and more consistent moisture can help plants focus on establishing their roots before the heat of next summer arrives.
When planting in fall:
- Choose plants that are hardy for our climate.
- Dig a wide planting area rather than an excessively deep hole.
- Make sure the root flare is at or slightly above soil level.
- Water thoroughly after planting.
- Continue watering as needed until the ground freezes.
Just because the leaves are falling doesn’t mean the roots have stopped growing.
2. Plant Spring-Flowering Bulbs
Want tulips, daffodils, crocuses and other spring flowers?
Fall is the time to get them in the ground.
Spring-flowering bulbs need a period of cold temperatures to prepare for spring growth, making fall planting ideal in Boise.
Plant bulbs in groups or drifts for a bigger impact next spring, and choose a location with good drainage. Tulips, daffodils, crocuses, hyacinths and alliums can all add early-season color to your landscape.
A little work now means a big payoff when spring arrives.
3. Keep Watering Your Plants
One of the biggest mistakes gardeners make in fall is assuming plants don’t need water anymore.
They do.
Newly planted trees, shrubs and perennials especially need consistent moisture while their roots are becoming established. Even established plants may need supplemental water if Boise has a dry fall.
Before watering, check the soil. If it’s dry several inches below the surface, it’s time to water.
As temperatures continue to drop, adjust your watering schedule rather than stopping abruptly.
4. Protect Plants From Frost
Some plants can handle Boise’s cold temperatures better than others.
Before a freeze, take a look around your garden and identify plants that may need extra protection. Tender annuals, newly planted plants and certain vegetables may benefit from frost protection.
For plants that need protection:
- Cover them with frost cloth or another breathable material.
- Cover plants before temperatures drop and remove coverings during the day when appropriate.
- Move container plants to a protected location when possible.
- Avoid letting plastic directly touch plant foliage.
And don’t forget about your potted plants. Containers can get significantly colder than plants growing in the ground.
5. Bring in Tender Container Plants
Have tropicals, houseplants or other cold-sensitive plants spending summer outside?
Now is the time to start bringing them indoors.
Before bringing plants inside, inspect them carefully for insects or pests. Give foliage a rinse if needed and transition plants gradually when possible.
Not every plant needs to come inside, but tropical and frost-sensitive plants generally won’t appreciate a Boise freeze.
6. Clean Up Diseased Plant Material
Fall cleanup doesn’t mean removing every leaf and cutting every plant to the ground.
Instead, focus on what actually needs to be removed.
Remove plants or foliage showing signs of significant disease or pest problems, and clean up fallen fruit or heavily diseased debris.
Healthy leaves can often be left in place or added to your compost pile. Many beneficial insects also use fallen leaves and garden debris as winter habitat.
A little thoughtful cleanup is better than stripping the garden bare.
7. Add a Layer of Mulch
Mulch can be especially helpful as temperatures begin to fluctuate.
A layer of organic mulch around trees, shrubs and perennial beds can help moderate soil temperatures and retain moisture.
Just remember:
Keep mulch away from the trunk and stems of your plants.
Avoid creating a volcano of mulch around tree trunks. Instead, spread it evenly around the root zone while keeping the trunk exposed.
8. Pull Up Frost-Sensitive Annuals
Once frost has damaged warm-season annuals, it’s time to clean them out and make room for what’s next.
But don’t assume every plant needs to go immediately.
Cool-season plants such as pansies, violas and certain ornamental plants can continue adding color well into fall, and some can tolerate surprisingly cold temperatures.
The first freeze doesn’t necessarily mean the end of your garden.
9. Plant Garlic for Next Summer
Fall is also a great time to plant garlic in the Boise area.
Plant individual cloves in well-drained soil with the pointed end facing up, then cover them with soil and a layer of mulch.
Garlic planted in fall can establish roots before winter and continue growing once temperatures warm up in spring.
10. Check Your Irrigation System
Before winter arrives, don’t forget about your irrigation system.
As temperatures drop, adjust your watering schedule and prepare your system for winter. Once freezing temperatures become consistent, properly winterize your irrigation system to help prevent damage from freezing water.
If you have an automatic irrigation system, make sure your controller is adjusted for the changing season.
11. Don’t Forget Your Soil
Fall is also a great time to think about the health of your soil.
Boise-area gardeners often deal with heavy clay soil, so improving your soil structure and organic matter can make a big difference over time.
Rather than simply filling a planting hole with a completely different soil, think about improving the broader planting area and creating conditions that encourage healthy root growth.
Your Boise Fall Garden Checklist
Before the first freeze, make sure you’ve:
☐ Planted fall trees and shrubs
☐ Planted spring-flowering bulbs
☐ Watered newly planted plants
☐ Protected frost-sensitive plants
☐ Brought tender containers indoors
☐ Cleaned up diseased plant material
☐ Added mulch around plants
☐ Removed frost-sensitive annuals when needed
☐ Planted garlic
☐ Prepared your irrigation system for winter
☐ Started preparing your soil for next season
Don’t Put Your Garden Away Yet
The first freeze doesn’t mean the gardening season is over. Fall is one of the best opportunities to prepare your Boise garden for a healthier spring.
Whether you’re planting a new tree, adding spring bulbs, refreshing a garden bed or looking for plants that can handle the Treasure Valley climate, the team at FarWest Garden Center can help you choose the right plants and products for your landscape.
Stop by FarWest Garden Center in Boise and let’s get your garden ready for winter.