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.
A combination of protective row covers, mulch, and drip hoses will dramatically reduce water loss.
Hot weather drains garden plants dry and reduces productivity, especially when rain is scarce. More and more gardeners have had to change the way they grow because heat and drought limit the season. Rather than getting discouraged, they have learned smarter gardening techniques and how to stretch resources. Approaching the garden season with several lines of defense for drought is essential, especially where summer water restrictions are usually imposed.
US Drought Severity is Growing
Drought patterns in the US, last updated on 10/04/22. (Image thanks to the NDMC, SOAA, and USDA)
The problem is growing. In much of the American West and some eastern states, summer brings seasonal drought at different levels of intensity. According to NASA’s Drought Monitor, a third of the United States was faced with drought in 2020. They stated, “Anestimated 53 million people are living in drought-affected areas.” It is a sobering number that shows no sign of decline, and it suggests that water-wise gardening has become a necessity for lots of American gardeners.
Keep Water Grounded
Professional growers opt for drip irrigation because it saves water and money. Home gardeners should do the same. Cover with a little straw, and it will hold water even better!
The first tips for saving water involve keeping it in the soil, while avoiding any aerosol or evaporative water loss from sprinklers or over-exuberant hand watering.
1. Amend soil with water-holding additives. Some soil components naturally hold lots of water and act as water reservoirs that make it more available to plant roots for longer. Organic matter (peat, compost, leaf mold, and coconut coir) is on the front line of holding water in the soil. Aerated organic matter soaks water up like a sponge and easily redistributes it to plant roots, For example, processed coconut coir soaks up 90% of its weight in water. Inorganic soil additives, like water-holding crystals and vermiculite, also hold water but are better suited for container gardening.
2. Use drip irrigation: Drip irrigation, in the form of drip-tubing systems for containers or drip hoses and drip tape for beds, deliver water at soil level where it quickly soaks into the ground, and is not lost by evaporation. Drip systems are the best for delivering garden water. In contrast, sprinklers lose an excessive amount of water to evaporation, and water delivery is not targeted.
Large, light-colored, ceramic pots hold water better and stay cooler.
4. Choose larger pots or containers that are glazed or water-impermeable and light in color. Large planters that are light in color hold more water better. Glazed or other water-impermeable surfaces keep the water in, unlike common unglazed Terracotta, which is porous and quickly loses water from its sides. Lighter pots also reflect heat, which helps keep plant roots cooler and happier.
5. Track Watering and Water Deeply: Keep track of watering time and length to determine the general amount needed to keep your garden happy. Soil moisture meters for pots make it easy to know when it is time to water, which takes the guesswork out, though most planters need daily watering when it is really hot and dry. When it comes to garden beds, water deeply–for at least a couple of hours–to ensure that water penetrates down to the roots. Deep watering also encourages deeper rooting, which helps plants get through tough, dry weather.
Manage Light to Reduce Water Loss
Lightweight floating row cover cloth, like this, or movable hoops covered with lightweight row cloth, can really help some crops withstand high heat and drought.
5. Reduce excess sunlight with light hoop covers. When temperatures are scorching and the sun is hot, floating hoop covers draped with lightweight row-cover cloth can be placed over small beds or low-growing garden vegetables to give them a rest and help conserve water. They will still get the light that they need, but the heat will be reduced a bit. Covers secured at both ends can also be helpful in keeping pests away. Greens, carrots, beets, turnips, and comparable crops appreciate this sort of light protection the most. (Click here for more row cover basics.)
6. Use strategic shading and timing. Plant perennials or pots in locations where they get some shade during the hottest time of the day in summer (between 2 and 4 pm). This will help them hold onto water when the weather is most extreme. Watering in the early morning, before the sun rises, will also help plants make it through hot, dry days. If you live in an area where the drought is bad, feel free to irrigate plants in the evening without fear of encouraging diseases. When it is severely hot and dry, plants need lots of moisture at the root zone to fill up with water and keep cool.
Collecting Water for Reuse
When rain does fall, it is wise to set up ways to collect runoff water–such as rain barrels or cisterns. Before doing so, one must know their roof composition beforehand because two roof types release high concentrations of dangerous heavy metals. These are roofs made of 1) uncoated galvanized metal, which releases high concentrations of zinc, and 2) treated wood shakes that release high concentrations of copper. All other roof types should be fine, according to research. Be sure to keep the tops covered to avoid mosquito breeding and possible animal drownings. Here is a little more information about these water collecting reservoirs.
7. Collecting water in Rain Barrels or Cisterns: Rain barrels are quite inexpensive and easy to install for rainwater collection. They connect to gutter downspouts to capture roof rainwater. Not only does this reduce watering costs, but many plants prefer rainwater over tap water. I recommend placing barrels up on cinder blocks to improve water flow from the release valve at the base. It makes it easier to fill watering cans or hook up hosing for garden irrigation. Be sure to empty your rain barrel at the end of the season if you live in an area with cold winters.
Cisterns are water collectors that store more water, and they may be kept above- or below-ground. They may be designed to collect rainwater, air-conditioning condensate, or even reserves of well-water. Unlike rain barrels, they are more costly to install but recommended for areas where water is limited and restricted. If you live in a place with annual seasonal rainfall of 15-inches/year or more (click here to see US annual rainfall averages), then consider installing a rainwater cistern.
Grow Drought-Tolerant Plants
Western hyssops (Agastache spp.) are some of the most beautiful, drought-tolerant garden flowers for pollinators that you can grow,
Some plants use water more efficiently or hold onto it better when the rain stops falling.
8. Grow Drought Tolerant Plants. Plants from the Mediterranean and arid West, as well as succulents, tend to shine in heat and drought. Those naturally adapted to more severe drought are often labeled as Xeric or Waterwise plants, and many specialty nurseries carry them. High Country Gardens is one great commercial online seller and Xera Plants is another. Most garden retailers these days also carry lots of drought-tolerant plants. Specialty succulent nurseries, especially those with lists of hardy plants, are also worth looking into. I like Mountain Crest Gardens. Their plants always arrive in great shape and perform beautifully. There are many more out there! Click on the links below for more drought tolerant plant resources.
“I read that Thyme can repel deer from your veggie garden. Is it true?” Question from Sylvia of Belle Plaine, Minnesota
Answer: Thyme is a mint, and on the whole, deer dislike the strong smell of many plants in the mint family (Lamiaceae), so mints, like thyme, can repel deer. But, I cannot say whether repellent mints would keep deer away from vegetables that they really love, like sweet potato vine. I recommend experimenting with a few to see if they help.
Here is a list of seven great minty perennial garden plants–both herbal flowers and culinary herbs– known to repel deer.
Hyssop (Agastache spp.): These sun-lovers have pretty flowers that bees, butterflies, and hummingbirds will visit. The pretty ‘Blue Fortune‘ will survive to zone 4.
Mints (Mentha spp.): Hardy peppermint, spearmint, and pineapple mint are all great options, but these fast-spreading plants must be grown in large pots (never the ground!) to keep them from taking over.
Monarda (Monarda hybrids): These beautiful summer flowers for pollinators have a strong smell that deer cannot stand. Plant them alongside your vegetables.
Catmint (Nepeta hybrids): The blue flowers of these hardy, bushy perennials (Zones 3-8) add great color to gardens. Proven Winners’ ‘Cat’s Pajamas‘ is especially pretty.
Rosemary (Rosmarinus officinalis): For northern gardeners to successfully grow this favorite Mediterranean herb, I always recommend the hardier variety ‘Arp’ (Zones 6-10). If you live in a colder zone, bring it indoors in winter.
Sage (Salvia officinalis): Pots of hardy sage (Zones 4-10) should help protect your vegetable garden and help flavor your favorite winter dishes.
Thyme (Thymus spp.): All thymes are repellent to deer, so plant away.
I hope that they do keep deer out of your vegetable garden!
“I have phlox growing in a big container. The bottom leaves are looking mottled/veiny. I have fed them and also added iron, but it doesn’t seem to be improving. Is there something else it needs?” Shawn from Kenosha, Wisconsin
Answer: Tall phlox (Phlox paniculata) varieties are prone to a series of diseases and foliage disorders, but yours sounds like it is physiological leaf blight of Phlox. It is a physical disorder caused by a water imbalance in the plant that can occur in some tall phlox varieties. Water circulation goes haywire–causing water to bypass the older leaves and only supply water to the new shoots. Here are the symptoms and solutions for this disorder:
Physiological Leaf Blight of Phlox Symptoms
Mature clumps are most often affected.
Lower leaves become mottled with prominent green veins before they eventually shrivel and die.
New growth is not impacted.
Physiological Leaf Blight of Phlox Solutions
Cut plants back at the end of the growing season, yearly.
Mulch plants to conserve water.
Water a little bit extra–though this only works in mild cases. Sometimes the circulatory disorder simply disables older leaves from accessing water.
“My succulent house plants have dry leaves in the middle of the stem and black spots. Why is this happening?” Question from Karina of Wenatchee, Washington
Answer: Succulent plants can develop dry leaves when they are being either overwatered or underwatered. The black spots and the fact that leaves are drying and dying in the center of the stem indicates stem and root rot, which is caused by a fungal infection that develops when plants are being overwatered. (Click here for some great images of overwatered succulents.) Sadly, central spotting and leaf death is an indication that your plant is dying and will not recover.
“How and when do you pinch dahlias to encourage fuller growth?” Question from April of Dresden, Tennessee
Answer: Once your dahlias are close to their final height (which depends on the variety) and have ample foliage, you can pinch or trim them back to encourage fuller growth, more branching, and more flowers. Just be sure to wait until they are large and full enough to bounce back nicely.
I always recommend cutting them back just above a branching stem node (see adjacent image). New branching stems will arise from the node. I also recommend using sharp shears to do the job rather than pinching (Corona Flora Scissors work very well). Cleaner cuts help plants heal and revive more quickly.
“I have a St.Theresa grapevine that has grown and produced very well. After being devastated by Japanese beetles last year, it developed several distorted leaves. Is it possible the Japanese beetles gave it some virus or disease? I cut it way back. Now, this spring, it has been making a comeback. But I noticed yesterday that some of the leaves at the ends of the new growth look distorted and discolored again. They look like the pictures of Eutypa Dieback. Help! What do I do?” Sharon of Colorado
Answer: Japanese Beetles (Popillia japonica) have been reported to vector some bean viruses, but there is no report or research to support that they spread any diseases of grape (Vitis vinifera). What is more likely is that your vines were weakened by the damage, left more prone to infection, and they obtained a disease. Other grape pests, such as mites, also spread grape diseases and they could have been the vestors. Either way, there are several grape diseases that can cause leaf distortion and discoloration. Here are some possible foliar grape diseases along with identification tips and management suggestions.
Grape Foliar Diseases That Cause Distortion
Grape Anthracnose (Elsinoe ampelina, fungal) causes symptoms on both leaves and fruit. Foliage will appear spotted and have brown lesions that cause leaves to curl. The grapes also develop dark lesions. Apply a Bordeaux mixture spray or Liquid Copper Fungicide to infected vines when they are dormant.
Eutypa dieback (Eutypa lata, fungal disease): Leaves can appear stunted, curled, and cupped. It is easily identified by cutting a stem: infected wood will have a wedge of darker, discolored wood against healthy, lighter wood. It infects older vines that are over five years of age. There is no known cure, so infected vines must be removed.
Viral Diseases: There are many viral diseases of the grape that cause leaf distortions. (Click here for a visual guide of grape viral diseases.) All are incurable, so I recommend removing any vines that you are certain are infected with a viral infection.
Getting outside help is my ultimate recommendation. The best way to firmly identify your grape disease is to send a sample to your local extension agent and have it tested in a lab. (Please click here to search for your local extension agent!) Definitive results are necessary because you do not want to destroy your grape if it has a curable disease.
“I have been given a rain barrel, but don’t have gutters on my house. How can I gather rain in my rain barrel without gutters? Thank you.” Jenifer of Saint Petersburg, Florida
Answer: That is a tough one. Rain barrels are made to collect water from the large surface area of a roof. Gutter downspouts have always been the water delivery system for rain barrels. You may consider getting gutters on one side of your house if you have a pitched roof.
Otherwise, I recommend finding the spot below your roof from which water drains the most. If you have a barrel that opens from the top, you can take the top off and then strategically place it below the drainage area for water collection. Place a mesh cover over the top to keep mosquitoes from breeding and animals from falling in and drowning. Because this method will reduce water collection, you may consider placing the barrel on stones or cinder blocks to increase water pressure and flow from the valve. Otherwise, you might consider giving the barrel to a friend with gutters.
“My peonies are more luxurious than ever this year. However, after the 1st rain, they tend to fall over. I have each bush encased in an upside-down tomato cage, but they still tend to droop, as the flowers are so heavy. Any suggestions to make this stop from happening every year and any ideas on how to make the glorious blossoms last longer? Many thanks!!” Question from Diane of Newark, Ohio
Answer: Sadly, this is a common problem with old-fashioned, double-flowered peonies. Their weighty blooms cause the weak stems to bend, so they droop. After a rain, the flowers hold water like petaled bowls, which causes them to drop to the ground. Tomato cages can certainly work, but some garden supply companies make even stronger perennial cages that do the job better. For example, Titan Peony Supports get high ratings from gardeners. Another option is to bolster each flower stem with its own stake before blooming begins. This method takes more time but results in a prettier-looking peony.
Finally, if your peony is planted in partial sun, it may be worth the effort to dig its massive root ball in fall and move it to a sunnier spot. More sun also encourages stem strength. Just be sure not to plant peonies too deeply (more than 3-inches below the surface) as this can inhibit flowering.
As far as making the blossoms last longer, there is no method known other than picking the blossoms for indoor arrangements and giving the cut flowers fresh water and cut-flower food until they fade.
“I live in zone 8 and have Blueberries. Do you prune Blueberries, and if so when?” Question from Lynn of Sacramento, California
Answer: Blueberry pruning is done to maintain crops as well as shrub shape and size. There are several rules when it comes to pruning blueberries. First, wait until shrubs are mature and fruit-bearing (at least five years old) before pruning for the first time. Next, like most fruit-producing shrubs, you need to wait until after their fruit has matured to prune. Blueberries produce flowers on old wood, so if you prune any later than post-fruit production, you will remove next year’s flowers. It is also essential to maintain strong fruiting wood, while removing weaker, spindly stems.
Four Blueberry Pruning Guidelines
Here are four guidelines to follow when pruning blueberries.
Prune just after berry harvest.
Maintain one strong fruiting cane (branch) for each year of growth, starting in the shrub’s fourth year.
Older canes can be replaced by stronger, newer fruiting canes after the shrubs have reaches 8-10 years.
Remove smaller, weaker, lateral branches to encourage stronger fruiting branches.
