Black hollyhocks are dreamy towers of stunning color and provide a hint of vintage cottage garden essence to your backyard. Whether you're a first-time gardener or a seasoned pro, growing these dark beauties can come with a fair share of questions.
In this article, I’ll share everything I learned on my journey to growing black hollyhocks, from their growth cycles to the best planting practices.
I started growing black hollyhocks in my garden a few years ago to satisfy my young teenage goth self and my current crunchy homesteader dye nerd.
Here’s a collection of tips and tricks that have worked for me, along with answers to some of the things that initially confused me about black hollyhocks.
Can I Just Scatter Hollyhock Seeds?
Yes, you can scatter hollyhock seeds on the soil surface, especially in the fall. This replicates how they propagate so readily in home gardens.
However, if you’re just starting out with hollyhocks, I recommend sowing them indoors in seed starting trays first. You’ll get better germination results that way.
I've tried both scattering seeds and starting them indoors. While scattering can work, it didn’t work for me. Maybe seeds got washed away in the fall rains. Starting them indoors yielded almost 90% germination in each seed cell.
Do Hollyhock Seeds Need to be Cold Stratified?
I got great germination results cold stratifying my black hollyhock seeds for 2 weeks. I simply put the seed packets in the fridge before surface sowing seeds in trays.
How Deep to Bury Hollyhock Seeds?
Hollyhock seeds prefer some light to germinate, so surface sowing is the way to get better results. I've always had good luck just lightly pressing them into the soil.
Should I Soak Hollyhock Seeds Before Planting?
Soaking hollyhock seeds overnight can speed up germination. It's not necessary, though—I didn’t do this and still got good germination results.
Where Is the Best Place to Plant Hollyhock Seeds?
Choose a sunny location with well-draining soil. My hollyhocks planted in a spot that gets 4 more hours of sun a day bloomed 2-3 weeks before they did in a shadier spot. Hollyhocks do best in spots with good air circulation to prevent fungal diseases, but not too much wind so that they don’t topple over.
How Many Hollyhock Seeds Per Hole?
Plant 3+ hollyhock seeds per spot to help each to have at least 1 successful germination. I usually over-plant and then thin them out, just make sure I get as many viable plants as possible.
What Do Hollyhocks Look Like the First Year?
In their first year, my hollyhocks formed a rosette of large, heart-shaped leaves. They stayed low to the ground, which made me wonder if they were growing properly, but they were just getting established.
How Do You Care for Black Hollyhocks as They Grow?
In the first year, I noticed my hollyhocks developing rust spots. I learned the hard way that watering at the base and providing good air circulation are key to preventing this issue. I also pruned off the lower leaves that showed signs of rust.
For my plants, rust didn’t end up impacting their ability to bloom in their second year.
To manage hollyhock rust naturally, consider using neem oil or creating a homemade garlic spray. Additionally, maintaining garden hygiene and proper plant spacing can significantly reduce disease occurrence.
How Many Years Does It Take Hollyhocks to Bloom?
Typically, hollyhocks bloom in their second year. I planted mine out as transplant seedlings, and over their first growing season developed foliage. Spring of their second season they send up tall leafy stalks that eventually formed buds and bloomed.
How Do You Keep Hollyhocks Blooming All Summer?
Regularly remove spent flowers, a process known as deadheading, to encourage continuous blooming. This step helps the plant redirect its energy from seed production back to flowering.
The plant will do this for you, though—I often find flowers around my hollyhock plants. Additionally, providing regular water keeps them healthy and productive.
Bonus: Hollyhock blooms make an excellent botanical dye, so you can do something with those spent flowers!
What Month Do Hollyhocks Bloom?
In my zone 7 garden, hollyhocks started to bloom in early July in my sunnier spots, and mid-July in my shadier spots. Seeing them bloom really made it worth the wait! Hollyhocks should continue to bloom until your first frost.
How Do You Keep Hollyhocks From Falling Over?
I’m actually surprised at how strong these plant stalks are! Just a couple of them have fallen over. An easy solution is to provide a stake or trellis to help them lean up against something.
Should You Cut Down Hollyhocks in the Fall?
Yes, cutting back hollyhocks in the fall can help prevent disease and make way for new growth. Remove any diseased foliage and toss it in the garbage to reduce the risk of rust spreading (in other words, don’t put it in the compost or mulch with it).
Are Black Hollyhocks Perennials and Do They Come Back Every Year?
Most black hollyhocks are technically biennials. This means they typically produce foliage in the first year and flower in the second. Occasionally, they may give you a third year of blooming before dying off completely. However, because they reseed so readily, it often appears as if the same plants are returning each year, leading many gardeners to treat them as perennials. For a true perennial, the variety 'Blacknight' is an excellent choice. This type of black hollyhock will last for years in the garden and provides consistent blooms season after season. You can find 'Blacknight' hollyhocks from seed suppliers like Swallowtail Seeds.
Will Hollyhocks Spread?
Yes, hollyhocks can spread on their own by reseeding. They are prolific self-seeders, so you may find new plants popping up around your garden. They don’t spread through runners or pups, though.
Can Hollyhock Flowers Be Used in Arrangements?
Yes, hollyhock flowers are beautiful in floral arrangements. Cut the stems early in the morning for the longest vase life.
How Do You Propagate Hollyhocks from Cuttings?
While hollyhocks are typically grown from seeds, you can propagate them from root cuttings in late fall or early winter.
Can Hollyhocks Be Used for Dyeing Fabric?
Yes, hollyhock flowers can be used to dye fabric. The flowers produce a range of colors from pinks to purples. Have a look at my hollyhock dye experiments.
Incorporating black hollyhocks into your garden can be a rewarding experience with the right knowledge and care. Personally, I've found success by giving them plenty of sunlight, regular water, and watching out for signs of disease like rust. Whether you're battling rust disease or trying to get them to bloom all summer, the tips provided should help you succeed. They really are worth the wait!
