As we embrace the warmer months, it’s essential to consider the resilience of our garden plants against the rising temperatures. Heat tolerance is crucial for maintaining a vibrant garden during the hottest days of the year.
Let’s explore the best summer plants for your garden and yard, from sun-loving perennials to heat-tolerant potted plants.
Understanding Heat Tolerance in Plants
Plants’ remarkable ability to adapt to their environment is at the heart of their heat tolerance. Here are a few ways plants handle summer’s heat:
- Some plants develop deep root systems that dive into the soil, seeking out moisture during the driest days. This sustains them during droughts and lessens their reliance on frequent watering.
- Others have leaf surfaces that reflect the sun’s rays, keeping the plant’s internal temperature regulated. This natural sunscreen prevents the damage that excessive heat can inflict.
- Certain plants minimize evaporation by having smaller leaves or waxy coatings, ensuring they maximize every rainfall or watering session.
- Lastly, succulents store water internally for use later. This allows these plants to sustain themselves during the hottest months.
Most of the plants listed are pretty versatile and can adapt to various conditions, including those in the Pacific Northwest. However, their success will vary based on your specific local climate.
Understanding Microclimates in the Pacific Northwest for Garden Planning
It’s important to recognize that the Pacific Northwest is characterized by a diversity of microclimates, which can significantly influence plant success. These microclimates range from the mild, moist coastal areas to the hotter and sometimes harsher inland regions.
As you select plants for your garden, consider your location’s microclimate. Factors such as local variations in temperature, humidity, wind, and soil moisture will affect the performance of certain plants.
For example:
- Coastal areas: Plants that tolerate humidity and salt are preferable. Depending on how exposed your garden is, wind-resistant varieties might also be necessary.
- Mountainous regions: Look for plants that can handle cooler temperatures and potentially shorter growing seasons.
- Urban areas: Heat-tolerant plants are ideal due to the urban heat island effect, which can cause higher temperatures in city settings.
By considering these factors, you can choose plants that are beautiful and well-suited to thrive in your garden’s unique environmental conditions.
Best Heat-Tolerant Flowers and Perennials
Selecting heat-tolerant flowers and perennials ensures your garden remains lively and colorful during the hotter months and supports sustainable gardening practices.
Lavender
This perennial favorite is renowned for its delightful fragrance and striking purple flowers.
- Lavender excels in full sun and well-drained soil.
- Once established, it requires little water, making it excellent for heat-tolerant landscaping.
- It might struggle in more humid or excessively wet areas unless drainage is very good.
Echinacea (Coneflower)
Echinacea brings a range of pink, purple, and white to the garden and is valued for its medicinal benefits.
- This North American native attracts butterflies and requires minimal water once established.
- These plants do well in most areas because they’re hardy and adaptable to various soil conditions.
- It tolerates the Pacific Northwest’s temperature variations and can handle the winter cold.
Gaillardia (Blanket Flower)
Gaillardia features vivid red, orange, and yellow blooms that reflect the intensity of the summer sun.
- These plants are well-suited to full sun and poor soil conditions
- It’s drought-tolerant and can handle the summer dry period.
Russian Sage
Russian Sage is beautiful and robust with its airy, lavender-blue flowers and silvery foliage.
- This plant is suitable for the Pacific Northwest as it handles both summer heat and cold winters well.
- It prefers dry conditions and full sun and blooms from mid-summer to fall.
Salvia
Salvia plants are favored for their vibrant flower spikes in shades of blue, purple, red, or white, attracting bees and butterflies.
- Salvia thrives in heat and dry conditions, perfect for creating striking borders and beds in hot climates.
- It needs good drainage and prefers sunny spots, which might be challenging in more shaded or constantly wet areas.
Sedum (Stonecrop)
Known for its water-retaining succulent leaves, Sedum is common in rocky or garden areas in the Pacific Northwest. They bloom from late summer to early fall, providing color and texture when many other plants begin to decline.
- Sedum is very suitable due to its drought tolerance and ability to thrive in poor soils.
- It’s notably low-maintenance plants and ideal for sunny, dry spots.
Zinnia
Zinnias are among the easiest flowers to grow from seeds. They come in various sizes and colors, offering numerous options for brightening garden spaces.
- Zinnias are highly heat-resistant and are perfect for sunny garden spots.
- To ensure they flourish, place them in areas that receive full sunlight and protect them from the heavy rains.
Read Low Maintenance Summer Flowers and Drought Tolerant Perennials for more heat-loving flower ideas.
Best Heat-Tolerant Shrubs and Bushes
Choosing heat-tolerant shrubs and bushes ensures your garden remains lush and beautiful throughout the summer while being manageable and resilient to rising temperatures.
Boxwood
Boxwood shrubs can be pruned into neat hedges or topiaries, offering structure and a classic look to any landscaping design.
- Boxwood shrubs are adaptable and heat-tolerant.
- It tolerates a range of soil conditions and can handle the moist, cooler climate of the Pacific Northwest.
Oregon Grape
This native Pacific Northwest shrub, with its holly-like evergreen leaves, provides year-round interest. In early spring, it produces yellow flowers, followed by dark blue berries that are attractive to birds.
- Oregon Grape thrives in both full sun and partial shade, making it versatile for different garden settings.
- Once established, the plant is also known for its drought tolerance, yet it can handle the moist conditions typical of the region.
Pacific Ninebark
Pacific Ninebark is a native shrub known for its appealing natural form and ability to attract butterflies, bees, and birds. In the spring, it blooms with clusters of white to light pink flowers, followed by interesting reddish seed capsules that persist into the winter.
- Pacific Ninebark is a hardy shrub that handles heat well and is tolerant of various soil conditions.
- This bush thrives in full sun to partial shade and is adaptable to dry and moist soil conditions, although it prefers well-drained soils.
Rhododendron
Rhododendrons are known for their spectacular spring blooms in various colors.
- These are evergreen shrubs that thrive in part shade to full sun, depending on the variety.
- It prefers well-drained, acidic soil and can handle the cooler, wetter conditions typical of the Pacific Northwest.
Rosemary
More than a culinary delight, Rosemary is a drought-resistant shrub that adds fragrance and a touch of Mediterranean style to gardens.
- Its needle-like leaves and blue flowers make it perfect for hot, sunny spots, and works well in borders or herb gardens.
- It may struggle in colder, wetter parts of the region unless given excellent drainage.
Read Shrubs & Flower Combination Ideas to plan your yard and garden.
Best Heat-Tolerant Vines
Choosing heat-tolerant vines that also thrive in the Pacific Northwest involves finding species that can handle moderate to warm summer temperatures and cooler, wetter conditions.
Boston Ivy
Boston Ivy is valued for its lush, green foliage, which turns brilliant shades of red and orange in the fall.
- This vine can grow in full sun to partial shade and isn’t picky about soil.
- It sticks to surfaces via suckers, making it easy to grow on walls or fences.
Clematis
Known for their spectacular blooms, many varieties of clematis do well in the Pacific Northwest.
- They prefer their roots to be cool and shaded while their tops enjoy the sun.
- These vines thrive in well-drained soil and benefit from mulching at the base to keep roots moist and cool.
Honeysuckle
Honeysuckle vines produce sweetly scented flowers that attract pollinators and can handle the heat when it comes.
- Honeysuckle performs best in full sun to partial shade and is not particularly fussy about soil type.
- It needs moderate watering but is somewhat drought-tolerant once established.
Trumpet Vine
With its showy, trumpet-shaped flowers, the Trumpet vine is a fast grower that can quickly cover large areas, attracting hummingbirds.
- This vigorous vine thrives in full sun and can tolerate heat very well.
- Trumpet vines can thrive in various soil types as long as they are well-drained.
Wisteria
With its stunning cascades of flowers, wisteria can create breathtaking garden features on pergolas and walls.
- It requires a sunny spot and a sturdy structure for support, as it can become quite heavy.
- Ensure it’s well-pruned to control growth and promote flowering.
For more help with vines, read Choosing & Growing Vines and Growing Vines from Seed.
Best Heat-Tolerant Vegetables and Herbs
Focusing on heat-tolerant plants allows gardeners to maximize their yield and enjoy a variety of fresh, home-grown produce throughout the summer months.
Basil
Known for its robust aroma and flavor, basil thrives in the heat, which helps intensify its essential oils. It’s an excellent companion plant for tomatoes and peppers in the garden and the kitchen.
- Plant basil in a location that receives at least six hours of direct sunlight daily.
- These herbs like well-drained soil enriched with organic material.
- Water basil plants in the morning to allow leaves to dry during the day.
Peppers
Peppers are versatile and colorful, ranging from sweet bells to spicy chilis.
- Peppers need plenty of sunlight, warmth, and regular watering.
- In especially hot climates, some afternoon shade can prevent overheating.
- Growing peppers in raised beds or containers can improve drainage and soil warmth, promoting better growth.
Tomatoes
A staple in summer gardens, tomatoes thrive in warm conditions. To get the best out of your tomato plants, start them indoors early or purchase young plants to transplant after the last frost when the soil has warmed up.
- They perform best in full sun, with ample space around them to enhance air circulation and reduce disease risk.
- Applying mulch helps maintain soil moisture and control weeds.
- Ensure consistent watering to avoid fruit cracking.
- Supporting the plants with stakes or cages is crucial for managing growth and boosting fruit production.
For more on vegetable plants, check out the Companion Planting Guide with Chart!
Best Heat-Tolerant Plants for Containers and Pots
Container gardening is an excellent option for those with limited space, such as patios, balconies, and small gardens. Selecting the right heat-tolerant plants is key to creating vibrant, thriving potted gardens in warm conditions.
In addition to many of the flowers and perennials listed above, here are a few other plants suited to tolerate heat in containers and pots.
Geraniums
Known for their durability and colorful blooms, geraniums are well-suited for containers.
- Geraniums require simple care – adequate sunlight and occasional watering are enough to keep their eye-catching flowers blooming all summer.
- These flowers prefer well-draining soil and should be moved to sheltered locations during particularly wet weather.
Herbs
Herbs like thyme, rosemary, and oregano are useful in the kitchen and thrive in hot, sunny conditions, making them great for container gardens.
- These Mediterranean herbs generally do well in heat since they like full sun and have moderate water needs.
- These herbs can thrive in the Pacific Northwest’s summer, provided they’re placed in well-draining soil and sunny locations.
Lantana
This plant is known for its clusters of small, vivid flowers and its ability to attract butterflies, making it a lively addition to any container garden.
- Lantana loves the heat, tolerates drought, and is generally low-maintenance.
- In cooler, wetter climates of the Pacific Northwest, lantana can be grown annually or moved indoors when temperatures drop.
Petunias
Petunias are a top choice for summer containers. They come in many colors and patterns, making them ideal for adding a splash of vibrancy to hanging baskets or elevated planters.
- They need full sun to bloom, so placing them in the sunniest parts of the garden or balcony will help them thrive.
- They may need protection from excessive rain, which can damage the flowers.
Drought and Heat-Tolerant Plant Care Tips
Creating a thriving garden with drought and heat-tolerant plants requires more than selecting the right species. It involves specific care techniques that enhance these plants’ resilience.
Soil
Proper soil preparation is crucial for the success of drought and heat-tolerant plants.
- Ensure your garden has excellent drainage, as waterlogged soil can lead to root rot and other issues.
- Incorporate generous amounts of organic matter, such as compost, into the soil. This improves soil structure, increases nutrient content, and enhances the soil’s ability to retain moisture.
Mulch
Mulching is highly effective in conserving moisture, suppressing weeds, and regulating soil temperature.
- Materials such as shredded bark, straw, or leaf mold keep the soil cool and moist and break down over time, adding nutrients back into the soil.
- Mulch also reduces the soil’s exposure to the sun to help decrease water evaporation.
Water
Efficient watering practices are key to the success of drought-tolerant gardens.
- Rather than frequent shallow watering, opt for less frequent but deep watering sessions to encourage the development of deep root systems.
- Read our guide,Water Saving Tips for Your Garden, for a deeper dive into watering during the summer.
For more tips on summer gardening, check out our June, July, and August Garden Checklists!
Cultivating a Summer Resilient Garden
By choosing plants adapted to withstand high temperatures and dry conditions, you can create a garden that survives and thrives despite the challenges posed by the summer heat.
Happy gardening, and may your green spaces flourish in the warmth of the summer sun!
Wilco, Professional Potting Soil
Not available online.
{{storeQuantity}} in stock in {{wg.store.city}}
Limited stock in {{wg.store.city}} Check nearby stores
Out of stock in {{wg.store.city}} Check nearby stores
Not carried in {{wg.store.city}} Check nearby stores
Cannot be sold in {{wg.store.city}} Check nearby stores
Wilco, Organic Potting Soil
Not available online.
{{storeQuantity}} in stock in {{wg.store.city}}
Limited stock in {{wg.store.city}} Check nearby stores
Out of stock in {{wg.store.city}} Check nearby stores
Not carried in {{wg.store.city}} Check nearby stores
Cannot be sold in {{wg.store.city}} Check nearby stores
Wilco, Premium Soil Test Kit
Not available online.
{{storeQuantity}} in stock in {{wg.store.city}}
Limited stock in {{wg.store.city}} Check nearby stores
Out of stock in {{wg.store.city}} Check nearby stores
Not carried in {{wg.store.city}} Check nearby stores
Cannot be sold in {{wg.store.city}} Check nearby stores
WFS, Garden Trowel
Not available online.
{{storeQuantity}} in stock in {{wg.store.city}}
Limited stock in {{wg.store.city}} Check nearby stores
Out of stock in {{wg.store.city}} Check nearby stores
Not carried in {{wg.store.city}} Check nearby stores
Cannot be sold in {{wg.store.city}} Check nearby stores
WFS, Fiberglass Handle Shovel
Not available online.
{{storeQuantity}} in stock in {{wg.store.city}}
Limited stock in {{wg.store.city}} Check nearby stores
Out of stock in {{wg.store.city}} Check nearby stores
Not carried in {{wg.store.city}} Check nearby stores
Cannot be sold in {{wg.store.city}} Check nearby stores
