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If you love flowers, it is but a short step to growing your own flowers. If you are fortunate enough to have loose, rich, dark soil, you are lucky. Pretty much all kinds of flowers will grow in that soil. If you have clay soil, like us, then we have a few challenges to work through. However, be confident that you will be able to get your flowers to grow. It takes a few more steps, but abundant blooms are in your future.
Let’s dive in.
Table of Contents
A quick look at soil
There are four basic types of soil: silt, loam, clay, and sand. The first two are full of nutrients and easy to grow in. I’ll note here that I am jealous of you if this is your soil. No wonder everything grows easily for you.
Now, sand is exactly what it sounds like—think of the beach—and it has very few nutrients and very little grows in it. Clay, which we have, takes more work and a little more knowledge to get things to grow. However, clay soil has nutrients and some benefits as well.
4 key identifiers for clay soil
Clay soil is reddish in color.
It absorbs water slowly and takes time to dry out.
Clay soil clumps together and sticks to gardening tools.
It can get very crusty and hard, and clay soil will crack when dry, particularly in the summer.
Sound like something you have dealt with in your garden? Don’t despair. There are ways to deal with this, and knowing about the soil helps.
What is clay soil like in the summer?
We have seen the soil become very hard in the summer, where you do not see a footprint and it feels as if you are walking on concrete. Our area can go 6-8 weeks without noticeable rainfall in the summer, so the soil becomes quite brick-like. How to get plants to thrive?
How to counter the natural hardening effects of clay?
We have three primary ways to help keep the ground good for growing flowers throughout the season:
- Lay a 1-2 inch thick layer of compost over the area where you are planting. This gives the seeds or young plants a chance to develop roots through soft, loose soil which is filled with nutrients. This gives your plants an important head start on their growth. Using a layer of compost also takes away the need to try to work the soil, which can compact it more than it might help.
- Provide a layer of mulch around the plants to help hold moisture in and to shade the roots. We use dried leaves as mulch. The leaves will naturally break down over the course of the growing season. We collect piles of leaves in the fall to use for the following year, both for creating compost and using for mulch. This also helps suppress weeds.
- Be sure to mound the soil and compost slightly so that any water drains away from the plant. You do not want a puddle around the plant, as flowers do not like wet roots. Since clay soil already holds onto water longer than loamy or silty soil, standing water can cause mold, fungus, or root rot issues.
You will need to do this each year, each time you plant. Clay soil has the talent of taking all the compost or soil amendments and absorbing them. By the next growing season, it is impossible to tell that anything was done to the soil. Clay soil is special that way.
Do flowers need a lot of fertilizer?
It is a lot of work for plants to grow flowers, so some fertilizer is welcome. However, you do not need to go crazy with this. Flowering plants in containers need a monthly boost of fertilizer, but not plants in the ground. A layer of compost at the beginning of the season is sufficient to carry the plants through the growing season. It’s another reason we like leaf mulch; it acts as a slow-release fertilizer as it breaks down over the growing time. Remember, your clay soil has nutrients in it as well.
Keep in mind that clay soil holds on to fertilizer longer than other types of soil, so you do not want to over-fertilize. Plus, clay soil has a lot of nutritional value.
If you have annual flowers that continue blooming through the fall, you could add a light fertilizer in early August as a boost. Most of the time, it is not necessary. We do not bother to add fertilizer in the middle of the season.
In general, you do not want to fertilize perennials at the end of the season, as they are getting ready to go dormant for the winter.
If you are working with flowers that need a more acidic soil, add sulfur. If you want a more alkaline soil, add some lime. Most soils do well with a pH in the neutral range, around 7.0. It is worth having your own soil meter to check soil temperature and pH.
Transplant or direct seed?
Because clay soil can be so difficult for seeds to break through, and because we experience periods of drought at unexpected times now, we transplant most of our flowers, including snapdragons, zinnias, lisianthus, dahlias, baby’s breath, gomphrena, celosia, and ageratum. Sunflowers prefer to be directly seeded, but we have also transplanted sunflowers as well. Note on sunflowers: since they have a long root, transplant before they are too big or you will have transplant shock.
For anything that you direct seed, it helps to have a layer of soft soil for the seeds to go into. The layer only needs to be 1-2 inches thick, enough for the seeds to get started. Remember, you only need to help the seeds get started, and then the plants will be able to cope with the clay soil.
How much water do the flowers need?
Access to water is very important. Mature plants need an inch of water each week—if it rains, you are off the hook—but young plants can dry out quickly in windy weather or a sudden hot day. They may need watering two or three times in a week. It will depend on the weather conditions.
In general, you want a watering system that delivers water to the roots, rather than overhead. Overhead watering, including rain, can damage the flower heads. If you want to sell the flowers, this is critical to have beautiful blooms. Drip irrigation or soaker hoses work well for flowering plants. This is an investment that is well worth it.
Do you want perennials or annuals for a cut flower garden in clay soil?
Both annuals and perennials can produce abundant blooms in clay soil. They each have advantages and disadvantages.
Perennials have a shorter bloom time, but you only have to plant one time. They can multiply so that you wind up with more plants than you started. The downside is you have to maintain the growing area during the non-bloom period with watering and weeding.
Annuals have to be started each year, but typically have a longer bloom period, often for the entire growing season.
You can always have some of each. It will all depend on what you are using the flowers for, what kind of vase life they have, and how much time you have for maintenance.
What are some general flower growing tips?
Look for hardy varieties that do well in your growing climate.
We love lisianthus because it is cold hardy, hot tolerant, and blooms from spring through the end of fall.
Sunflowers are great because they do not need staking, they can be densely planted, and there are a lot of varieties and colors to spice up your offerings.
Staking saves your plants in wind and rain. As the flowers mature, the heads are heavy, and it is too easy for the whole plant to blow over in a storm. Staking saves months of work so that you can continue to harvest.
Consider having certain flowers for different times of year. Not all varieties last for the whole season.
If you have somewhere under cover, you can plant bulbs for late fall or very early spring flowers, as they will grow even with fewer daylight hours.
FAQs
Q: Will flowers grow in clay soil?
A: Yes, with a little help for seedlings and knowledge about water.
Q: Should you direct seed or transplant into clay soil?
A: It is easier for seeds and seedlings to grow into a layer of compost on top of the clay soil and establish roots. You can direct seed or transplant.
Q: Do flowers need more water in clay soil?
A: Clay soil holds onto water longer than other soil types.
Q: Does clay soil get too hard for flowers to grow?
A: Protect the plants’ roots by adding an inch or two of leaf mulch to cover the area where the roots grow. This helps reduce watering and keeps the roots cool during hot summers.
Conclusion
Growing flowers in clay soil can be rewarding, as long as you take the steps to amend the soil and protect the plants and their roots. The results will be abundant and beautiful. Have fun growing!