Zinnias: A Family Favorite in the Garden and Home

By Jay White, Contributing Writer

I can honestly say that I have never had a garden without zinnias. I am not one of those gardeners who enjoys growing fussy plants. That’s why zinnias are welcomed back into my gardens each and every year.

Zinnias are (almost) fail-proof flowers that come in about a million different sizes and colors. Their upright stalks, with alternating leaves, make them so easy to cut and strip for the homemade arrangements my wife and I love to make. Plus, they are resistant to most pests, tolerant of some drought and an absolute magnet for bees and other pollinators.

With all they have going for them, it is easy to understand why zinnias are about the only plant that I guarantee you will find in my garden each and every year.

For years I grew whatever zinnia seeds I found on the rack at my local nursery or big-box store. Then, while doing an article for this magazine, I interviewed a commercial flower farmer who introduced me to the variety that I now grow almost exclusively. ‘Benary’s Giant’ is the zinnia variety that the pros grow.

Kim Haven of Billabong Fresh Cut Flower Farm in Hempstead, TX, gave me some of her seeds. While I was a generic zinnia lover before, Kim’s seeds turned me into a zinnia connoisseur. Since ‘Benary’s Giant’ is so lovely, and works so well as cut flowers, I don’t think I will ever grow another variety.

In the ground

The zinnias most of us grow are cultivars of the species Zinnia elegans. While there are varieties that grow all over the world, Zinnia elegans originated in Central America and Mexico. Because of this, they love the full sun and hot temperatures that abound in the southern United States.

If you are going to grow your zinnias in the ground you can start your seeds after the soil warms up to around 70 degrees. In Zones 8 and 9, that can happen by mid-to-late February. While you can plant your zinnia seeds that early, I always wait until the middle of March to try to avoid any late-season freezes. While zinnias are tough plants, they do not like the cold. A light freeze can kill newly sprouted zinnias.

Zinnia seeds need light to germinate, so do not plant them too deep. Cover your seeds lightly with no more than a quarter-inch of soil. You can plant them by hand by spacing your seeds 6 inches apart for smaller varieties and one foot apart for larger varieties like ‘Benary’s Giant.’

If you need to cover a large area with zinnia seeds, I suggest using a steel rake to make little furrows over the area that you are planting. Then, after scattering the seeds out in a broadcast manner, flip the rake over and drag the flat side over the area. This method is very quick and it seems to get just enough soil over the seeds to ensure good germination.

However you plant your seeds, you need to water them regularly for the first couple of weeks. While mature zinnias can withstand some dry periods, germinating plants need a nice even supply of moisture to allow them to become well established. I use a spray nozzle to lightly water in the seeds and young plants. For the first couple of weeks, I water enough to keep the soil moist but not soggy. Depending on the air temperature, you may have to water daily.

If the soil is warm enough, your first sprouts should appear in about seven days. Once they are up let them grow to about 3 inches before thinning. If you planted at the recommended spacing, then you do not need to do this. However, if you used my broadcast method, you will need to thin your plants to the recommended 6 inches for smaller varieties and 12 inches for the bigger varieties.

After thinning your plants, you can reduce their water to about an inch every five days and also begin feeding them.

All blooming annuals benefit from ample nutrition while they are producing their beautiful flowers. Despite how often you fertilize, or how good you think your soil is, most Texas soils are nitrogen deficient.

To produce super-healthy plants that produce lots and lots of beautiful flowers, you will more than likely need to apply some supplemental nitrogen while they are actively growing. When they get ready to bloom, their need for nitrogen decreases while their need for phosphorous increases.

Because annuals grow so quickly, it is a good idea to feed your flowers regularly with a balanced fertilizer. Most organics are fairly balanced and you almost cannot over-apply them. Unfortunately, they can be a bit expensive. Because of this, I side-dress my plants with various dry organic products no more than once a month.

If you water regularly and feed occasionally (and the weather cooperates), you can have your first zinnias about 60 days after germination. If you regularly cut the flowers (or deadhead the spent blooms) and feed them monthly, you can theoretically keep them blooming until the first frost.

In reality, after about three months, pests and age begin to take their toll and these annual plants begin to look rather haggard. Because of this, I pull them and replant.

From transplants

The fastest way to get some annual color in your beds and borders in the spring is to plant transplants.

Each spring I am amazed to see flats of zinnia starts for sale at the nurseries. While there is nothing wrong with this, zinnias are so easy to grow from seed that it just seems like a waste to spend so much on so few plants. With a little timing and a little effort, you can easily turn a $1.99 pack of seeds into two or three flats worth of plants.

Start zinnia seeds inside in February and those transplants can realistically produce some flowers by early April (depending, of course, on the weather). I grow my transplants in plastic starter trays that I purchase off-season. 

Zinnias take about 60 days from seed to flower, so you can start your seeds about a month before you are ready to transplant. I usually let my seeds grow in my starter cells for about four weeks before I put them out.

I use a lot of my flowers in arrangements, so I will often replant my zinnias two or three times a year (I also do this with sunflowers and cockscomb). Growing my own transplants allows me to economically provide myself with a steady supply of fresh-cut flowers.

 

In containers

While I grow my zinnias in the ground, they also do well in containers or raised garden beds.

Large varieties like ‘Benary’s Giant’ or ‘California Giant’ (another favorite) produce flowers that are 3 to 4 four feet tall. Because of this, they do best in the ground.

However, growers have been working to create smaller varieties like the ‘Pinwheel’ mix (from Burpee) and the ‘Magellan’ mix (from Park Seed) that do great in containers. These little zinnias get about only a foot tall. However, their flowers are just as pretty and they bloom just as prolifically as their bigger cousins.

Mildew

Zinnias are amazingly resilient flowers. They can take some overwatering and they can withstand some periods of drought. They are not overly bothered by too many insects.

However, some of the older varieties are very prone to mildew infestation. Mildew will cause their leaves to brown and curl, and can eventually kill the plant. The best way to avoid this is to water from below with drip lines or soaker hoses. If you have to water from above, water in the morning so the sun can thoroughly dry the foliage during the day. If you do all of this and still have mildew problems, look for a newer variety. Most of the newer varieties have been bred for mildew resistance.

Pest control

As odd as this may sound, I use zinnias as a pest-control method in my vegetable garden.

Several years ago a gardener told me that a row of sweet, nectar-rich flowers in your garden reduces the number of pests that munch on your vegetables. Supposedly, many of the bugs that are feasting on your tomatoes, beans and squash would rather sip the sweet nectar of flowers.

Ever since I heard this I have grown a mixed row of flowers in my vegetable garden. To be honest, I am not 100 percent certain this works. However, being certain is not really that important to me. My flowers look great in the vegetable garden and they make me feel like I have fewer bugs on my tomatoes, beans and squash. So, until someone proves me wrong, I am going to continue growing zinnias as a pest-control method.

Cutting

I grow a lot of zinnias every year. I grow them to use in cut flowers for my house and I use them to make arrangements for my family and friends. In the past, I have also grown them to be used in one daughter’s wedding.

As I mentioned before, their long, straight stems make zinnias one of the best cut flowers the homeowner can grow. One thing that makes zinnias so good for home arrangements is the fact that they will last for several days in the vase.

To get the longest life out of your cut flowers, cut them in the early morning. Cut above a node to encourage branching and more blooms. Once you cut the flower, grasp it with your thumb and forefinger right under the flower head. Then, grasp the stalk with your other hand and pull straight down to remove all of the leaves. Once the stems are stripped, drop them immediately into a bucket full of fresh, clean water. Finally, transfer to a vase with the proper amount of flower food.

Family favorite

While I enjoy growing zinnias, they have a much deeper significance for my mother. She is convinced that I would not have had a little sister if it weren’t for these tough, colorful flowers.

Let me explain.

My little sister was adopted. Due to complications caused by my birth, another child was a dream that could only come true for my parents with the help of an adoption agency. If you have ever adopted a child, you know that it is an arduous process that requires lots of paperwork, background checks and home visits.

My parents wanted this child so much, so my mother always worked very hard to make the best impression possible when the agency folks came to visit. These visits always warranted my mother’s best dishes, her best cutwork tablecloth (handmade by my grandmother), her sweetest tea and a large bouquet of zinnias from her yard.

My parents were lucky enough to get my sister in record time and with an absolute minimum of fuss. My mom still swears that the process went so smoothly because the adoption agent loved her tea parties so much. I have tried to tell her many times that the hassle-free adoption had more to do with the fact that she and my dad were pretty good people who lived a very good life.

However, she refuses to hear it. To her, she got her daughter because of Southern charm, hospitality and a big bunch of zinnias.