“How do I know what zone I am in for growing specific plants and trees?” Question from Kathy of West Rutland, Vermont
Answer: The USDA Hardiness Zone map, which helps gardeners determine what perennials, trees, and shrubs will survive the cold in their area, is available online. Click here to view the map. All you need to do is add your zip code, and the database will provide you with your hardiness zone. It is as simple as that!
Happy gardening,
Jessie Keith
Black Gold Horticulturist
“Can I get rid of Liverwort by burying it in the ground?” Question from Russ of Berkley, California
Answer: It depends on the site’s soil, soil level, and moisture level. Admittedly, I kind of like the common liverwort (Marchantia polymorpha). Sorry! But, they’re kind of cool. The funny little non-vascular plants are close relatives of mosses and a sign of a very moist, shaded, nutrient-rich garden area. With that said, I dislike it when they grow in containers, so I understand why you don’t want them in your garden. Here are some different options for liverwort removal.
The number one way of ridding liverwort from an area is to reduce moisture and fertility, increase soil drainage and aeration, and increase light if you can. (They can’t tolerate dryness or high sunlight.) You can do this by lifting your garden soil in the area where they are causing trouble and adding aggregate to the soil to improve drainage.
Another option is to dig up the liverwort, lift the soil, and plant the area with garden plants for your area that will tolerate moisture and shade. Here are a couple of options.
Wood strawberry (Fragaria californica): The California native wood strawberry produces fruit, likes shade to partial shade and grows well in moist soils. It forms an edible groundcover, which might appeal to you.
Idyllwild rock flower (Heuchera hirsutissima): Here is an upland California wildflower that can tolerate moist and dry planting areas as well as partial shade, and it’s very pretty.
Pigsqueak (Bergenia crassifolia): Though it is not native, Bergenia is a pretty evergreen perennial for the shade that produces clusters of pink flowers in late winter and early spring. It likes moist, well-drained soil.
Click here for lots more shade plant options from the California Native Plant Society.
There are approved liverwort controls that contain vinegar, and apparently, they are very effective. (Click here for more information.) I also recommend that you click here to read an excellent overview of liverwort control in greenhouses from Oregon State University. It covers cultural controls as well as chemical ones.
I hope that these liverwort management tips help!
Happy gardening,
Jessie Keith
Black Gold Horticulturist
“We will be planting roses on the north side of the house this summer. We have clay soil. What do you recommend mixing into the soil?” question from Roseanne of Rockford, Illinois
Answer: Roses grow and resist disease best when grown in full sun. The north side of your home may not be the best spot for roses unless you plant them far enough from the foundation to get enough full sun. Hydrangeas, fothergilla, glossy abelia, summersweet, and sweetspire are better flowering foundation shrubs for the north side of a home. I recommend that you calculate what garden areas along that side of your home get at least six hours of sun per day. (Eight hours is better.) Roses won’t perform well with less.
When it comes to the soil for roses, good drainage and good fertility are essential. If your soil is heavy clay, it will require lots of amendments to get it in shape for roses. Please read the following articles to learn how.
Roses prefer soil with a slightly acid pH of 6.5, so peat moss is a recommended amendment. You also have the option of building your soils up and berming along your foundation to lift your soils to facilitate better drainage. We also suggest that you fortify your newly planted roses with alfalfa meal (3-1-2), a natural fertilizer that’s great for roses.
I also encourage you to watch the video below about growing roses organically.
Happy rose gardening!
Victory Gardens inspired millions of Americans that had never gardened to grow food to feed their families. Everyday people learned to garden on a homesteading scale. And, my family was no exception. My maternal grandparent’s Victory Garden taught them to fend for themselves, and eat well when wartime rations were most limited.
“Does laying down newspapers diminish weed growth as well as laying down weed mat?” Question from Barbara of Afton, New York
Answer: It’s an excellent question. They can both work very well. I have a love-hate relationship with mulch cloth/mat that does not organically break down over time. It helps keep back aggressive weeds, like Canada thistle, in the first season, but then it quickly becomes an annoying, useless layer of plastic that weeds grow into. I don’t care for plastic or porous Tyvec cloth getting in the way of my gardening. It’s expensive and has limited efficacy.
Then there’s newspaper, thin cardboard, and burlap weed fabric. I like these options better because they break down over time and create a good, natural base to give mulch extra weed-smothering power. Once they are gone, you simply reapply them once more.
If you opt for newspaper, which is nice because it’s essentially free, use at least three layers of black-and-white print paper and wet them down before applying them to cleaned garden areas. Thin cardboard should also be wetted. Then simply top the paper with a 2-3-inch layer of leaf mulch, bark mulch, pine straw, or whatever mulch cover you prefer. (Click here to learn all about different mulch types.) In my opinion, paper is the best option for smaller garden spaces.
Burlap weed fabric costs money and is slower to break down, but it works. It is also better for covering larger garden spaces. Apply it where you need it and then apply mulch as needed.
In my garden, I tend to prefer products that are natural. And newspaper can even save you money.
I hope that these tips help.
Happy gardening,
Jessie Keith
Black Gold Horticulturist
“What are the best perennial plants to use for foundation planting? [I need] something to cover a fairly tall, 5ft swath of concrete foundation. Thank you!” Question from Trish of Newton, New Jersey
Answer: There are lots of wonderful garden perennials ideal for foundation plantings. Those that I recommend the most are long-lived, have a long season of beauty, and perform reliably. When designing a perennial garden for a foundation, It’s always important to plant larger perennials towards the back, graduating to shorter specimens towards the front. Here are some options that mix well together and look great.
The perennials listed here are bold, bushy, look good all season, and create good foundation coverage while also creating a nice backdrop for shorter perennials.
Line the edges of your beds with perennial sedums, low-growing flowers and ornamental grasses, or anything colorful or evergreen. Lots of creeping garden plants look great along a garden edge. (Click here to read more about garden creepers.)
I hope that you use some of these plants to design a spectacular foundation perennial border this year.
Happy gardening,
Jessie Keith
Black Gold Horticulturist
“What can I use for whiteflies on Jatropha plants?” Question from Susan of Pembroke Pines, Florida
Answer: I recommend physical methods of removal for whiteflies followed by the use of an insecticide approved for organic gardening.
Whiteflies are fast-to-produce sucking insects that remove the juices from plant leaves and stems. Tiny whiteflies can be very destructive when populations are high–causing leaf drop and decline. When plants are badly infested, the undersides of leaves will become covered with clouds of tiny white flies and clusters of their small, round, white egg masses.
Start by spraying the plants off with a sharp spray of water from the hose. Focus on the undersides of leaves. Then look beneath the leaves for clusters of small, white egg masses. Leaves thickly covered with egg massed should be removed, tightly bagged, and thrown away. Next, wipe the small numbers of egg masses off of the remaining leaves. Make sure no eggs remain. Finally, spray the plants with insecticidal soap or Neem oil. (Click here for an overview of horticultural oils for organic insect control.) Continue to check for whiteflies and wipe and spray leaves as needed.
It may take a little work, but this method is effective.
Happy gardening,
Jessie Keith
Black Gold Horticulturist
“I planted a chartreuse ground cover, I believe it was a sedum, not sure. Very low growing. It looked great & then the deer discovered it – they ate it all. Can you suggest another chartreuse ground cover that perhaps the deer wouldn’t – the little darlings.” Question from Peggy of Canton, Michigan
Answer: Many sedums are succulent treats for deer. It is really too bad because they are otherwise so tough and beautiful. There are a number of low, spreading groundcovers with chartreuse or golden-chartreuse color that deer tend to avoid. Here are some perennial options in addition to one woody option.
Golden Creeping Jenny (Lysimachia nummularia ‘Aurea’): Here’s a fast-spreading, non-evergreen groundcover that will withstand both partial sun and shade. It grows best in fertile soils and can take over quickly, so plan to dig some out on occasion to keep it in line.
Golden Spotted Deadnettle (Lamium maculatum ‘Aureum’): Spotted deadnettle is a pretty, fast-spreading flowering groundcover in the mint family. In general, deer avoid plants in the mint family. The variety ‘Aureum’ has very pretty golden-chartreuse leaves and pinkish flowers in spring. It grows best in partial sun to shade.
Good Vibrations® Gold Spreading Juniper (Juniperus horizontalis Good Vibrations® Gold): The beauty of this chartreuse groundcover is that it is evergreen. Each plant only reaches a little over 1 foot tall but can spread as far as 6 feet. It is very tough and thrives in full sun.
Banana Boat Creeping Broad-leaved Sedge (Carex siderosticha Banana Boat®): Plant this beautiful, deer-resistant sedge in groups to create a chartreuse and gold ground cover. It grows best in partial shade.
Golden Lemon Thyme (Thymus x citriodorus ‘Aureus’): Deer can’t stand the strong smell of thyme, and this sun-loving groundcover has the leaf color you want and is also edible. Just be sure to plant it in well-drained soil.
I hope that some of these suggestions interest you.
Happy gardening!
Jessie Keith
Black Gold Horticulturist
“I planted fava beans, and I noticed that I have ants on them. How do I get rid of them without using any unnatural pesticides?” Question from Isabella of Waxhaw, North Carolina
Answer: There are two possible reasons why ants may be visiting your fava beans, and in both situations, the ants are not doing damage. Here are the two possible scenarios and solutions.
Happy gardening,
Jessie Keith
Black Gold Horticulturist
“When should I prune lavender? I tried it at the end of summer last year, but I think I might have cut too far back.” Question from Manda of Florence, Kentucky
Answer: In my experience, lavender has the best regrowth results if one waits to prune until the plants begin to produce fresh spring leaves. It simply bounces back best when it has begun to actively grow. It is a warm-season perennial, so wait until April before trimming it.
The best pruning method is to cut the shrubby top growth back by 1/3, using sharp pruning shears. Try to keep the top rounded to maintain a pleasing, bushy habit. At this time, you will also want to remove any dead or dying stems. Don’t be tempted to cut it back further. If you prune lavender back too far towards the base, it can invite fungal disease and disable the plant from fully recovering to its former glory.
Happy lavender pruning!
Jessie Keith
Black Gold Horticulturist
