Plants, flowers and vegetables grow best in hardy zone 6b gardens!
My name is Juliea, and I live in the Treasure Valley of Idaho hardy zone 6b garden.
In zone 6b, We are lucky to live in a climate that can grow such a large variety of plants that aren’t tropical (and some that are!) I’m sharing what grows well here, and when to plant it in your garden!
In USDA hardiness zone 6b, the growing season typically starts in early May, depending on the weather conditions. This is when the last frost date has typically passed, and the temperatures are warm enough for many plants to start growing.
What to Plant Before Last Frost Date
It’s important to note that while these plants are more tolerant of cold temperatures, they may still require protection from harsh frost or freezes. Using row covers, frost blankets, or other protective measures can help ensure successful growth and yield.
There are several cold-weather plants that can be planted by seed outside before the last frost date, as they are more tolerant of cold temperatures. Here are some examples:
Late Summer Garden: These Plants Can Be Planted Weeks Before the Last Frost Date
- Peas: Peas are cool-season legumes that can be planted outside about 4-6 weeks before the last expected frost. They prefer temperatures between 40-70°F and can tolerate light frost.
- Radishes: Radishes are root vegetables that can be sown directly in the ground 2-4 weeks before the last frost. They can germinate in soil temperatures as low as 40°F and mature quickly, usually within 20-30 days.
- Spinach: Spinach is a cold-hardy leafy green that can be planted outside as early as 4-6 weeks before the last frost date. It prefers temperatures between 35-75°F and can tolerate light frost.
- Carrots: Carrots are root vegetables that can be sown outside 2-4 weeks before the last expected frost. They can germinate in soil temperatures as low as 40°F and mature in about 60-80 days.
- Lettuce: Lettuce is a cool-season leafy green that can be planted outside about 2-4 weeks before the last frost date. It prefers temperatures between 45-75°F and can tolerate light frost.
- Kale: Kale is a cold-hardy leafy green that can be planted outside about 4-6 weeks before the last frost date. It prefers temperatures between 60-70°F and can tolerate light frost.
Veggies to Plant Before Last Frost Date
- Beets: Beets are root vegetables that can be planted outside 2-4 weeks before the last expected frost. They can germinate in soil temperatures as low as 40°F and mature in about 50-70 days.
- Broccoli: Broccoli is a cool-season vegetable that can be planted outside about 6-8 weeks before the last frost date. It prefers temperatures between 60-65°F and can tolerate light frost.
- Cauliflower: Cauliflower is a cool-season vegetable that can be planted outside about 6-8 weeks before the last frost date. It prefers temperatures between 60-65°F and can tolerate light frost.
- Brussels sprouts: Brussels sprouts are a cool-season vegetable that can be planted outside about 6-8 weeks before the last frost date. They prefer temperatures between 60-65°F and can tolerate light frost.
- Onions: Onions are a cool-season crop that can be planted outside as soon as the soil is workable, usually a few weeks before the last frost date. They can tolerate temperatures as low as 20°F.
Vegetables, Herbs, and flowers that Grow in Zone 6b.
You can start growing these plants in late April – Early May. The local rule of thumb in my town is to plant starts after Mother’s day.
In USDA hardiness zone 6b, some of the first plants you can typically plant in late April to early May are cool-season vegetables and herbs, as well as some hardy annual flowers. Here are some examples:
Vegetables:
- Beans (bush and pole)
- Beets – One of my favorites!
- Broccoli
- Brussels sprouts
- Cabbage
- Carrots
- Cauliflower
- Corn
- Cucumber
- Eggplant
- Kale
- Lettuce
- Okra
- Peas (sugar snap and shelling)
- Peppers
- Pumpkins
- Radishes
- Spinach
- Summer squash
- Tomatoes
- Winter squash
- Zucchini
Berries
Strawberries – Learn How to Grow Strawberries
Raspberries – Learn How to Grow Raspberries here
Blackberries – Learn How to Grow Blackberries
Blueberries grow great zone 6b, but they need a more acidic soil. So I haven grown them here… Because I need to amend my soil for them first!
Herbs
- Basil
- Chives
- Cilantro
- Dill
- Lavender
- Mint
- Oregano
- Parsley
- Rosemary
- Sage
- Thyme
The best flower garden plants to grow in zone 6b include:
- Peonies: These large, fragrant flowers come in shades of pink, white, red, and yellow and bloom in late spring to early summer.
- Hydrangeas! These beautiful flowers are perennial so you only have to plant them once and they bloom all summer!
- Lavender! Lavender plants in zone 6b do well if they make it through their first winter… Some will not make it, but they are perennial and bloom till frost!
- Tulips: With their bright colors and unique shapes, tulips are a great addition to any garden. Plant bulbs in the fall for spring blooms.
- Daylilies: These easy-to-grow perennials come in a range of colors and bloom from early summer to fall.
- Black-eyed Susans: These bright yellow flowers with dark centers bloom in mid-summer and attract pollinators to your garden.
- Coneflowers: Also known as Echinacea, these pink, purple, or white flowers bloom in mid-summer and are great for attracting butterflies.
- Salvia: These tall, spiky flowers come in shades of blue, purple, pink, and white and bloom in mid-summer to fall.
- Liatris: Also known as Blazing Stars, these tall, spiky flowers have purple or white blooms that attract bees and butterflies.
- Alliums: These ornamental onions have round, globe-shaped flowers in shades of purple, pink, and white that bloom in late spring to early summer.
- Daffodils: These cheerful yellow or white flowers are a sure sign of spring and are great for naturalizing in a lawn or woodland area.
- Iris: These tall, elegant flowers come in a variety of colors and bloom in late spring to early summer.
These are just a few of the many beautiful flowers that can thrive in zone 6b. Be sure to choose plants that are suited to your specific growing conditions and soil type for best results.
Flowers to Gorw in Zone 6b
Zone 6b has a moderate climate, with cold winters and mild summers, so there are many beautiful flowers that can thrive in this region.
- Alyssum
- Calendula
- Cosmos
- Marigolds
- Nasturtiums
- Pansies
- Petunias
- Snapdragons
- Sunflowers
- Sweet peas
- Verbena
- Zinnias – These are beautiful show stoppers and cut flowers. Plus they’re super easy to grow from seed!
This is not an exhaustive list and the specific plants you can grow may depend on the microclimate of your garden and the years’ weather conditions in your area.
It’s always best to check with your local cooperative extension service or gardening center for recommendations specific to your region.
Want to learn more about gardening in Zone 6b? Learn more at https://www.youtube.com/@FarmhouseHarvest
