Plants are the lens Jessie views the world through because they’re all-sustaining. (“They feed, clothe, house and heal us. They produce the air we breathe and even make us smell pretty.”) She’s a garden writer and photographer with degrees in both horticulture and plant biology from Purdue and Michigan State Universities. Her degrees were bolstered by internships at Longwood Gardens and the American Horticultural Society. She has since worked for many horticultural institutions and companies and now manages communications for Sun Gro Horticulture, the parent company of Black Gold. Her joy is sharing all things green and lovely with her two daughters.
Can you plant annual flowers and vegetables in the same raised bed? Question from Diane or Newark, Ohio
Answer: Sure! In many cases, annuals can be beneficial to vegetables by warding off pests (click here to read about the protective power of marigolds) and/or attract pollinators. Compact flowers that will not compete for too much sunlight or water are best. Here are some of my favorite flowers to plant in my vegetable garden for beauty, cut flowers, and to feed pollinators. These sun-lovers are all effortless to grow.
Cosmos (dwarf): The pretty daisy flowers of these annuals are good for cutting and attract bees. Try the compact varieties Sonata Mix (2-feet high) or the fully double pink ‘Rose Bonbon‘ (2 to 3-feet high).
Calendula: These cheerful yellow or orange daisies are grown as herbs as well as flowers because they have edible petals that can be used to make tea or soothing balms.
Dahlias: There are hundreds of amazing dahlias to choose from and all make excellent cut flowers. Bees and butterflies also love them. Choose compact varieties for easier care. Check out Swan Island Dahlias to choose the best dahlia for your taste.
Marigolds: I love tall marigolds in the vegetable garden. The large flowers look pretty through summer, and these Mexican natives just thrive in the heat. ‘Kee’s Orange’ is a brilliant variety with deepest orange flowers.
Compact Sunflowers: There are loads of spectacular sunflowers for the garden, and all are very easy to grow from seed. I suggest choosing compact varieties because they won’t shade out vegetables or fall over in wind. (Click here to learn all about growing sunflowers.)
Zinnias: Any tall or medium-sized zinnia will add color and cut flowers to your garden. Check out the new Zinnia ‘Zinderella Purple’ or Zinnia ‘Queeny Orange Lime’. Both are beautiful and some of the easiest flowers that you can grow from seed.
Try adding any of these pretty annuals to your vegetable garden this season for functional color.
Do you think that you don’t have the time or patience to grow vegetables? Then check out these 10 really fast-growing vegetables. These provide harvestable produce in as little as 20 days. The list includes everything from zucchini to carrots and kale.
Popcorn cassia (Senna didymobotrya) is a tender garden plant for containers and gardens.
Gardeners are just beginning to learn about the benefits of adding bold, golden-flowered sennas to their gardens. These members of the pea family naturally fortify soils with nitrogen in addition to producing large clusters of brilliant gold flowers and lush foliage. They lend tropical good looks to landscapes and beds, and their flowers are also draw pollinating bees and butterflies. Some are even butterfly host plants.
Most sennas are long-blooming. Some are large, shrubby, and need space to grow. Others can be grown as tender perennials that stay small in summer, making them suitable for growing in flower borders or containers. Species exist worldwide, but quite a few are North American natives. Overall, sennas have the benefit of being very resilient and tolerant of high heat. Some are even desert plants perfect for xeriscaping.
Here are just a few attractive sennas to consider cultivating in your landscape or pollinator garden this season.
Sennas for Gardens
Popcorn cassia (Senna didymobotrya, USDA Hardiness Zones 9-11): This has become the most popular senna on the market. It is native to Africa where it grows as a large 6- to 8-foot shrub, but popcorn cassia works well as a tender perennial for containers and gardens. In the heat of summer, it bears nonstop candles of golden flowers that are dark in bud. Its flowers feed bees and butterflies, and it is also a host plant for various sulphur butterfly caterpillars. Cuttings can be taken in fall and overwintered for outdoor cultivation the following season.
Many sennas are host plants for various sulphur butterfly caterpillars, including the cloudless sulphur butterfly.
Feathery cassia (Senna artemisioides, USDA Hardiness Zone 8 to): With fine, silvery foliage and loads of fragrant golden flowers that bloom non-stop, this Australian desert plant grows best in arid to semi-arid regions, though it can also be grown as a container specimen, if provided very sharply drained soil, such as Black Gold Cactus Mix.
Feathery cassia (Senna artemisioides) is adapted to desert conditions.
Maryland senna (Senna marilandica, Zones 4-8): Native to open woods and dry roadsides across the eastern United States, this tall, tough perennial deserves more attention from American gardeners. It forms bushy clumps of compound leaves that may reach between 3 and 6 feet, depending on the selection. In July and August, it becomes topped with large clusters of flowers that may be pale yellow, golden yellow, or pale orange. These are especially attractive to bumblebees, and it is a host plant to sulphur butterflies. The flowers are followed by large, dark, pendulous seed pots. Plant it in spacious perennial borders where a large, impressive garden plant is needed.
Maryland senna (Senna marilandica) is a tall, very hardy North American species.
Silverleaf cassia (Senna phyllodinea, Zones 9-11): Another xeric species from Australia, silverleaf cassia is an exceptionally pretty bushy shrub with slender silver leaves. Its masses of golden flowers bloom from winter to spring. Grow it in southwestern gardens with rocky or sandy soils. It has the potential to be invasive, so plant it away from natural areas.
Golden Wonder Senna (Senna splendida, Zones 9-11): In warm-winter regions of the United States this South American tree senna produces large clusters of bright gold flowers from early fall to early winter. The trees can reach 16 feet and are semi-evergreen.
Golden Wonder Senna (Image by Alex Popovkin)
Cultivating Senna
Overall, sennas thrive in full sun. Dryland species require very well-drained soils, but all others will grow well in average fertile soil with moderate to good drainage. Amend the soil of in-ground plantings with plenty of Black Gold Garden Soil amendment, which has added fertilizer and rich organic matter. Container-grown popcorn cassia will thrive in large containers filled with Black Gold Natural & Organic Potting Mix.
Plant any one of these golden beauties in your hot summer garden for resilient plantings sure to draw lots of pollinators to your flower beds and landscapes.
“Do you have any idea what this orange-floweredshrub is?” Question from Donna
Answer: This pretty, drought-tolerant bloomer is a hybrid orange Scotch broom (Cytisus ‘Lena’). It’s sweet-pea-like orange and orange-red flowers flower from May to June, and its fine green stems are lined with small leaves. This shrub is tolerant of wind, salt spray, and infertile, well-drained soil. Most brooms can be quite invasive, but this pretty hybrid has sterile seeds, so it won’t self sow.
“I am pregnant and was watering my plants when I got Black Gold potting soil on my hands. I am concerned about toxoplasmosis and have questions. Is your soil made in areas where cats are present?” Question from Katie
With that said, be cautious when gardening while pregnant, and always wear waterproof garden gloves followed by washing your hands well after gardening. All natural, in-ground soils always contain Listeria monocytogenes, a bacterium that can cause the disease listeriosis, which pregnant women are susceptible to. So, dig carefully, and clean up well. (Click here to read the CDCs guidelines for protecting yourself from listeriosis.)
We also recommend washing any garden herbs, fruits, or vegetables very well before consuming them.
“I purchased 3.0 CF bags of Black Gold Peat Moss. What is the expanded volume of this bag? I need 3.5 cubic yards of peat for my raised bed garden mix, so was going to buy 32 of these bales…but realized it’s going to expand. How do I calculate how much to buy?” Question from Dave of Utah
Answer: To determine the expansion of 3.0 cubic foot bales of Black Gold Peat Moss anticipate it at a 2:1 ratio. So, the bales should expand to 6 cubic feet when properly fluffed. One cubic yard equals 27 cubic feet, so to determine the amount you need in cubic yards calculate 3.5 x 27 = 94.5. Then divide 94.5 by 6 for a total of 15.75 bales. I’d go with 16 bales of peat to be safe.
“The rainfall this year has been incredible and my window boxes are showing it. I usually take off the top of the soil each year and replace it with new soil but this year there is a lot of moss. I would like to know if I should just remove all of the soil and treat the containers or if I can just scrape the moss off and top the boxes off with new soil before planting.” Question from Melissa of McDonough, New York
Answer: All potting soil breaks down over the years, losing aeration, structure, fertility, and drainage capacity. The dense organic matter of old potting mix just sits at the bottom of pots and slows drainage. Mixes also tend to acidify as they age and break down. Moss grows best on more acid soils that are moist and high in organic matter, which is probably why your boxes have more moss than average.
Simply topping off your window boxes yearly will encourage shallow rooting because plants grow best in newer potting soil, and deep rooting encourages the best growth.
To avoid all of these problems, your potting mix should be replaced every two years or so. If mix from the previous year or two is not well aerated and porous when wet, then it’s time to replenish. (Instead of tossing old mix, I like to incorporate it into my beds as an amendment, so I don’t waste it.) In the process, make sure the holes at the bottom of your boxes are open and draining well. When replacing mix, it also helps to add an all-purpose, slow-release fertilizer.
“What are the spots on my dogwood tree leaves, and how can I prevent them? They come back every year.” Question from Jennifer of Ramsey, Indiana.
Answer: If you see no stem or branch dieback on your flowering dogwood, then it is likely suffering from spot anthracnose (Elsinoe corni), a fungal disease that is unattractive but NOT deadly, unlike dogwood anthracnose. Another possibility is Septoria leaf spot (Septoria cornicola). Spot anthracnose is a more common spot disease of dogwood, so this is likely what your tree is suffering from.
Spot Anthracnose Symptoms
The main symptom of spot anthracnose is lots of tiny spots on the leaves with dark purple borders. The flowers can also develop little brown spots. White-flowered dogwoods tend to get the disease more severely than pink-flowered varieties. This disease is most problematic when springs are extra cool and wet.
Septoria leaf spot produces larger purple spots that are more angular than round. It is also most problematic in cool wet weather. If this is what you believe you have, manage it as you would spot anthracnose.
Managing Dogwood Spot Anthracnose
This is a difficult disease to manage on large trees, but there are several measures that can help. First, the disease overwinters on infected leaves, so clean up all of your dogwoods leaves well in the fall. This is not a foolproof measure because the disease can also overwinter on fruits and buds, but it will reduce the amount of disease-causing material. In early spring, just as the flower buds begin to break and the leaves unfurl, spray your trees with a fungicide every week to two weeks throughout the early part of the growing season. This will reduce and help control its onset. Liquid copper fungicides and neem oil are two options approved for organic gardening that are reported to work.
If you are game to plant a new tree, there are also quite a few flowering dogwoods that are resistant to fungal spot diseases. These include the double-flowered dogwood ‘Plena’, the heavy flowering and disease-resistant ‘Cherokee Princess’, the deep-pink-flowered ‘Cherokee Chief’, and the hybrid Stellar Pink®, which has large, pale pink flowers.
Flowering purslanes are drought-tolerant, tough, succulent, and have ever-blooming flowers in a wide variety of brilliant colors.
“What are the best flowers to plant in hanging baskets for high desert? We have lots of wind also?” Question from Jill of Greybull, Wyoming
Answer: There are several options for you. All of the plants I will mention are tender in your area. Some can be brought indoors to overwinter while others are best treated as flowering annuals. In this list, I avoided the common hanging succulents, like string-of-pearls and donkey tails, because they lack impressive flowers. (Click here to learn more about these hanging succulents.) Regardless of the drought-tolerant status of these hanging flowering plants, all will still require regular daily water in the growing months. They will also need to become well-rooted and established in their baskets before they are fully tolerant of dry heat and winds.
Plant all of these hanging basket plants in a moisture-holding potting mix so they can grow to their fullest outdoors. I recommend Black Gold Waterhold Cocoblend, which is OMRI Listed for organic gardening, or Black Gold Moisture Supreme Container Mix. I also suggest hanging them along a porch or patio where they will get some protection from the high midday sun. If you bring any of them indoors as winter house plants, water them very little during the cold months because this can induce rot. (Click here to learn more about winter succulent care.)
Here are a few long-blooming hanging basket plants to consider for your high-desert garden.
Hanging Drought-Resistant Flowers
Firecracker plant trails beautifully and grows well in containers and hanging baskets.
Firecracker plant (Russelia equisetiformis): Hummingbirds love the flowers of this trailing Mexican native. It has very fine foliage and becomes covered with red, tubular flowers all season long, with good care. It is tolerant of both wind and drought.
Trailing lantana (Lantana sellowiana): This extra drought-tolerant lantana produces many clusters of white-eyed lavender flowers that are visited by butterflies. It grows well as a seasonal ground cover but also looks great in hanging baskets.
Cobweb spiderwort (Tradescantia sillamontana): The silvery leaves of this drought-tolerant spiderwort from Mexico are lovely, and it bears lavender-pink flowers from early to midsummer. It also makes a great house plant.
Silverleaf geranium (Pelargonium sidoides): This tough, droughty geranium has pretty silver leaves and dark red flowers that bloom nonstop if you remove the old flowers. It grows well as a groundcover but also looks lovely in hanging baskets and containers. You can also bring this one indoors in winter.
Hanging Flowering Succulents
Flowering purslane (Portulaca umbraticola): You will want to grow these beautiful succulent annuals for their brilliantly colored flowers. They are perfect for hanging baskets and bloom all season long. You can also try the common and closely related moss rose, but it is a little less drought tolerant.
Little pickles (Othonna capensis): This succulent from South Africa has starry yellow flowers that bloom all season. It also makes a lovely house plant.
I hope that you try some of these beautiful hanging basket plants in your high desert garden this season.
“What are the best vegetables for cool summer areas?” Question from Angie of Fort Bragg, California.
Answer: The classic cool-season vegetables are cole crops (cabbage, broccoli, cauliflower, collards, and kale), root crops (turnips, beets, onions, and spring carrots), and greens (lettuce (see video below), spinach, arugula, and Swiss chard), but there are also typically warm-season vegetable varieties specially bred for cool-season growing. Here are some that you are less likely to know about. (Click here to learn more about growing cole crops)
Corn: Likewise, there are fast-to-produce corn varieties bred for cooler climates, such as ‘Northern Xtra-Sweet Hybrid‘ and ‘Early Sunglow‘. These will produce sweet ears reliably and very quickly.
Cucumbers: ‘Early Fortune’ is a crisp, sweet cucumber for slicing and pickling that was bred in Michigan to bear quickly and thrive in cool weather. The English cucumber ‘Early Pride‘ is another good selection.
Squash and Zucchini: The best squash and zucchini for your growing needs are bush varieties that produce in as little as 45 days. Try the classic zucchini variety ‘Green Machine‘ or the beautiful yellow pattypan summer squash ‘Sunburst‘.
Tomatoes: The golden cherry tomato ‘Sungold‘ is an early producer with tomatoes that stay sweet and flavorful, even in cool weather. The red slicing tomato ‘New Girl‘ is another early producer to try that has the added bonus of good disease resistance. Finally, ‘Polbig‘ is a quality bush tomato with red fruits that was specially bred for cool-summer growing.
