With the exception of a few very warm days, the 2020 coastal spring has been a good one. If only one could bottle up nighttime temperatures in the low 60s and daytime temperatures in the mid-70s and release them at will throughout the long summer here!
I doubt any of us relish the many days of temperatures above 85°F that are soon to come and that will remain into October with an average of 70 of those days being above 90°F. That is just plain hot, for any living creature and for many plants.
I have a philosophy about gardening as a result of such temperatures. Plan wisely in early spring, choosing heat-tolerant plants and get them all planted by the end of May. Many spring offerings in garden centers won’t make it through to October; I start to scout out the plant selections in late April and early May looking for those plants that will not only take the heat but also the intense sun. Most will still do best in moist, organically rich, well-drained soils and yes, they may even require watering in the longest of dry spells.
• 2020 Proven Winner Diamond Frost Euphorbia is a wonderful heat and drought tolerant plant with unique, airy white flowers that bloom all summer. It reaches 12-18 inches in height and spread. It looks delicate and frilly but holds its own in full sun, partial sun and light shade areas. It can be planted alone or in combination with a number of other flowering annuals.
• Evolvulus “Blue Daze” is a low-growing annual, reaching only about 12 inches in height with one-inch true blue flowers and small silvery-green leaves. It is a wonderful choice for a container or as a flowering groundcover at the garden’s edge.
• Madagascar Periwinkle (Catharanthus roseus) is a treasure in a summer with its endurance of high temperatures, drought and nutritionally deficient soils. New varieties are always being introduced such as the Vitalia Collection from Sakata Ornamentals and the Soirée collection from Suntory. Flowers are outstanding with phenomenal coverage as long as the plants are in full sun. Insects and deer stay away. Keep in mind, Periwinkle is absolutely intolerant of poorly drained soils or overwatering! Available in upright and hanging forms.
• Pentas (Pentas lanceolata) has an abundance of star-shaped flowers that bloom all summer long in shades of pink, white, red and purple. The Glitterati Purple Star, introduced in 2018, offers a distinctive purple and white flower with a star pattern. Now, the new Glitterati Red Star is available to compliment it. All pentas plants attract hummingbirds and butterflies and are top performers in heat and humidity. Heights of different cultivars range from 18 to 24 inches in height.
• Gaura (Oenothera lindheimeri) is a clump-forming perennial with flowers that delicately bounce above the foliage atop long thin wiry stems, as if tiny butterflies were visiting. A common name is whirling butterflies; another name is bee blossom. Gaura develops a deep taproot, enabling it to withstand drought once established. It thrives in full sun, with little fertilization or care required. Strong plants will reach from 15 inches to 5 feet in height, depending on cultivar and bloom from mid-spring throughout the summer. Flower colors include white, soft pink and rose pink. Browsing deer may or may not nibble. I have seen it eaten to the base and in another season, it remained untouched. Too much water will kill this drought-tolerant native of Texas and Louisiana. Although our original plants of 2016 failed to come back after the first winter, they reseeded themselves. Subsequent plants have done the same, returning in early spring each year. New plants are in full bloom with some thin, erect blooming stems extending over four feet in length.
• Begonias are a mainstay in our garden. I have areas that get partial sun or dappled sunlight and the Red Dragon Wing is by far my favorite for those areas. If a spot gets morning sun, the bronze leaf begonias do well, but no begonia thrives in blazing direct all day sun. Begonias need shelter from drying soil and heat. I do love tuberous rooted double flowering begonias that I see offered in local garden centers, but I have not found them to thrive in my coastal garden. I do get to enjoy them every few years when visiting a friend in Seattle where she has them in hanging baskets throughout her spectacular landscape. Garden envy, sigh.
• Salvias still reign in my front garden, attracting warring male hummingbirds, butterflies and local honeybees. Ease of growing, intense and profuse color display, deer resistance and heat tolerance are top qualities. Height and flower colors vary. Some of my top perennial choices that come back year after year are Wendy’s Wish, Indigo Spires, Black and Blue and Amistad.
• Coleus offers so many leaf colors as well as a good variety of leaf shapes that I am sure every gardener can find at least one favorite one to plant in the coastal garden. Look at the various labels to see mature heights and planting location (full sun, part sun or shade).
• Lantana is a reliable heat and drought perennial and blooms throughout the warm months of the year. The older varieties can still be found growing in areas where a former home once stood. Personally, I have found newer types unreliable as perennials and quite susceptible to lace bug infestations (tiny flying insects that feed on the underside of the leaves and newly opened buds and flowers, severely stressing the plants which then stops blooming). However, there are insecticidal sprays that can control insect problems. Butterflies are attracted to lantana. A solid border of lantana is an amazing site in bloom.
• Ornamental peppers offer upright fruits in dazzling bursts of red, purple, yellow, orange, white and black. Many varieties offer fruit that change color as they mature. You can eat the very spicy fruit, but they lack flavor. These peppers like full sun, but don’t tolerate dry soil so keep their roots in rich, moist growing soil.
This short list of 10 plant choices is by no means conclusive. That is what is so much fun about gardening. It is a challenging and stimulating hobby that is never stagnant, continually offering new and different plants to keep one’s interest. There are the tried and true favorites, but experimentation should always play a role. Buy one new species this season and expand your gardening world.