Cut Flowers for High Tunnels: A Beginner’s Plant Guide

High tunnels offer protection from the elements, allow growers to extend their season, and take advantage of vertical space. Controlling the environment where our fruits, veggies, herbs, and flowers live hugely benefits yields, growth rate, and the quality of products we can provide. 

Growers worldwide continue to adjust growing conditions as our climate changes and becomes more unpredictable. Our food system’s resilience and security rely on this ability to shift, but let’s not forget about the flower farming world. 

In this article, small-scale farmer Jenna Rich spoke with Vanessa Campbell of Full Sun Farm in Big Sandy Mush, North Carolina. Campbell has been growing in high tunnels for over 15 years and selling her products at the longest-running farmers’ market in the state, the North Asheville Tailgate Market. She offers excellent insight on growing in high tunnels, shares tips and tricks, and speaks to the joys of producing high-demand flowers for her community. 

Why Use a High Tunnel for Cut Flowers?

As the demand for locally grown cut flowers and bouquets continues to grow, cut flower farmers have adopted high tunnels, which have many advantages. 

Advantages

• Increased control over growing conditions like irrigation and fertilization practices.
• Protection from pests increases the marketability of your product. Growers can monitor flowers closely as they grow and take swift action if pest control is necessary. 
• Protection from harsh weather like wind gusts, floods, drought conditions, and extreme temperatures 
• Higher yield and quality of blooms
• Extended seasons, growers in some markets can charge up to $3 per stem in the off-season. 
• More bang for your buck: Charge more for higher-quality products, and you can utilize the space more than once with early spring bloomers. 

Considerations

High tunnels are certainly an investment; there are aspects to consider before you plunge into high tunnel shopping. 

• Initial costs and investment
• Maintenance and operational needs
• Risk of tunnel damage in extreme weather 
• Increased land taxes may be applicable 
• Cost of building permits, if required 
• Changes your farm aesthetic 
• Requires building experience 
• You need to find your flower market to sell your product 

Read our article, “What You Need to Know for Successful Winter Growing in High Tunnels, Greenhouses, and Gardens,” for details on growing in high tunnels through the winter. 

Choosing Cut Flowers for High Tunnels

Market demand, personal preference, growth habits, and spacing are essential when selecting cut flowers to grow. We will discuss each of them here and then dive into some popular choice flowers that perform well in high tunnels. 

Climate Adaptability of Flowers for Your Growing Zone

When selecting flowers, consider your region’s climate. Sweet peas and feverfew, for instance, perform better in areas with long, cool springs, like New England. However, you’ll have to hold off on planting frost-sensitive dahlias in colder regions, but they’ll be off to the races in a North Carolina high tunnel in the spring with some added frost blanket protection. 

When trialing a new flower, learn about its ideal conditions, what temperatures it can survive, and what other growers are experiencing. If you have data on temperatures your high tunnel experiences, this will be helpful when selecting flowers. 

Pro tip: When a cold spell is forecasted, place low-tunnel hoops over your flowers, add a string of incandescent holiday lights, and cover the beds with frost blankets. The lights will add several degrees of much-needed extra heat overnight. Vanessa swears by this trick and claims it has helped early-season flowers survive temperatures of 17°F (-8°C). 

Market Demand for Trendy Flowers

While it’s difficult to forecast the market's demand for the following year, social media, seed catalogs, blogs, and your customers can help you predict up-and-coming trends. Local flowers will continue to be in high demand, so keeping your finger on the pulse of the flower farming world will help you increase sales and gain traction in your area as a reliable cut flower source. 

Pro tip: Vanessa says if something is trendy, but you don’t have experience growing it, don’t utilize indoor high tunnel space. First, try starting seeds and growing a small amount of these specialty flowers outside. Take notes on how it grows, performs, and sells. 

For example, Full Sun Farm used to grow an entire tunnel of lisianthus but struggled with thrips. They weren’t seeing enough profits for all the attention the flowers needed. They have since been moved outdoors and do great! 

Decide if the trendy flowers are worth the valuable tunnel space. Consider the additional heat of high tunnels; will they survive the fluctuations and extremes? Do they need the extra protection? Just because something is trendy doesn’t mean it’s right for your farm. Another option is growing it inside a caterpillar tunnel first, then transitioning them to the high tunnel if they perform well. 

Related: Season Extension on a Flower Farm

Grow for Market and for Yourself

We’ve all been there, growing things just because they’re in demand, but they’re no fun. Farming should be profitable and enjoyable, so while we just discussed market demand and growing what sells, find some joy in what you grow by adding some that are just for you. You may devote one bed to new varieties to trial or install a raised bed for your favorite tulip cultivar whose stems aren’t long enough for cut flower bouquets. 

Planning for the Growth Habits of Cut Flowers

Considering the growth habits of the flowers you’ve selected is essential when choosing your tunnel layout, planning necessary trellising, and pairing plants with similar needs. 

• Heat tolerance
• Height 
• Branching habits
• Lifespan
• Need for trellis or fencing 
• Bloom period
• Trailing or vining 

High tunnel space is expensive, and preparing garden beds is a lot of work, so these factors should significantly affect your decision to grow them in this prime farm real estate. For example, if something needs 8-foot trellising, a central bed will be less hassle than an outside bed near the wall. 

Planning for the Spacing Requirements of Flowers in a High Tunnel

Consider the growth habits and spacing when plotting out tunnel beds. Vanessa encourages new growers to be bold and plant flowers tightly, even though most things you read will tell you otherwise. She says the way to get exceptionally long stems and the most product from valuable high tunnel space is to plant everything at 6-inch spacing, four plants across. The competition for resources you’ve intentionally created makes them reach higher for the sun, resulting in long stems. Her one exception is feverfew, which requires more space to spread out. If your tunnel has proper ventilation control and air circulation, diseases shouldn’t be a significant concern.

Pro tip: Measure trellis netting, which offers the spacing you need, and connect it to two wooden stakes. When it comes time to transplant, lay the netting on the ground. The squares of the netting make for an even, straight grid without much effort. Roll it up and store it safely for your next transplant session.

Popular Cut Flower Choices for Growing in a Hoop House

• Anenome (Anemone coronaria): This popular poppy-like flower offers bold, bright shades, unique leaves, and fluffy centers. Each corm can produce 30 flowers. When harvested and stored correctly, anemones can last up to ten days in a vase. They are a reliable overwintered species and can be ready for Mother’s Day if planned correctly. 
• Dahlias (Dahlia): The world of dahlias expands yearly with over 10,000 varieties in the American Dahlia Society online classification guide. Their “jumping genes” make it easy to create new dahlia cultivars from seed each season, ranging in shape, color, size, and pattern.
  These tropical, tuberous perennials love heat and take a long time to mature, making them ideal candidates for high tunnel growing. Many dahlia varieties, especially dinner plate varieties, grow tall and may require staking. They are also vulnerable to damaging pests and diseases. 
• Lisianthus (Eustoma grandiflorum): These herbaceous rose-like plants are a hot commodity for their bold colors and unique, antique finishes. Each stem can feature up to five blooms, and they have a stellar vase life and long stems ideal for bouquets. Lisianthus, or lizzies as they’re lovingly called in the flower world, thrive in the heat a high tunnel provides.
  Lizzies are prone to rainfall damage, making them an easy pick for valuable high-tunnel real estate. Starting them from seed can be challenging for beginners, but plugs are readily available. 
• Ranunculus (Ranunculus Asiaticus): These cool-weather lovers grow from corms and are often called Persian buttercups. Treat them as hardy annuals for best results. Their extended bloom period lasts four to seven weeks, slightly shorter in warm regions with hot springs. Overwintered ranunculus have an extended bloom period compared to spring-planted corms. Growers adore ranunculus for their long vase life, intricate, multi-petaled blooms, and bold colors. Popular with wedding designers and florists. 
• Snapdragons (Antirrhinum): Snapdragons are the perfect complementary spike flower in bouquets, but they also look stunning on their own. Their delicate petals and sometimes slender stalks need protection from strong winds and hard rainfall, and they appreciate the stable environment a tunnel provides.
  Snapdragons can grow to five feet tall with the added heat, so support is required. Harvest often to encourage continuous blooms. Deadhead in the late summer for a second full flush, and they’ll continue producing until the first hard frost. 
• Stock (Matthiola iguana): Cold zone growers should consider these lush, versatile flowers with a sweet floral scent. Stock is a member of the cabbage family, so protect it from flea beetles and other early-season pests that attack Brassicas. Most are a column or single-harvest flower, so plant multiple successions for continuous blooms. There are also spray varieties that produce multiple smaller sprays of flowers.
  
• Sweet William (Dianthus barbatus): Sweet William, or Wee-Willies are hardy to Zone 4 and bloom early, making them the perfect overwintering high tunnel option. Blooms offer bright, cheerful colors and a unique clove scent. 
• Tulips (Tulipa spp.): Growing tulips in high tunnels and hoop houses speeds up the bloom time in USDA Zones 1-4. You can plant them directly in the ground in warmer zones. They need the freezing temperatures of winter to go dormant and bloom appropriately in the spring. If you live in a warmer zone you will need to prechill bulbs before planting. Check out our article, Growing Tulips for Cut Flower Production, for more details. 

Setting Up Your High Tunnel

Building a high tunnel is not for the faint of heart, but kits make it more approachable, and we’re here to help. Before beginning, confirm that you have all the required parts, read the instructions, prepare your site, and gather all the tools needed, including extra hands.  

Materials and Construction

Steel and aluminum structures will be the sturdiest buildings, essential to growers in areas with heavy snow loads and extreme winds. Before ordering a high tunnel, do your research, read testimonials, and get answers to all your questions. Ensure the tunnel comes with everything you need, like Bootstrap Farmer’s Greenhouse Kits, that the bracing and arch spacing align with your region’s needs, and that it’s NRCS-compliant if necessary. 

Vanessa remembers installing their first tunnel in 2010, whose sides rolled up manually until 2020. She recommends not skimping on elements you’ll use daily and requiring repetitive motions that could cause injury, like the manual roll-up sides with heavy, 100-foot-long posts. Automations are worth the up-front investment. Full Sun Farm’s original high tunnel doors were plastic held on by wiggle wire tracks, which she said should be well-constructed and sturdy to withstand wind gusts and general wear and tear. 

Choose a UV-resistant plastic built to last. It should be at least 6-mil thick and transmit enough light to allow healthy growth. Consider a double layer of plastic in areas with high snow loads and woven plastic for extra durability in areas with strong winds and difficult to tear. What is the Best Plastic Covering to Use for a Greenhouse? Our Guide to Greenhouse Plastic

The height you choose should allow you to grow the varieties you want and work within your property's boundaries. Consider building height regulations in the area you need to adhere to. 

Irrigation and Scheduling of Watering in High Tunnels

Drip line irrigation is the most common and effective way to water high tunnels. It’s efficient, practices deep watering, and can automate a schedule and distribute fertilizer. Deep watering is a method of irrigation that delivers water to a plant’s root zone without fear of evaporation. Keeping water off plants’ foliage also decreases the risk of fungal disease. 

Set timers to irrigate on whatever schedule you need. Some farmers water every other day for an hour or more each time, while others water for less time more frequently. 

Bootstrap Farmer’s Watering Timer - Two-Dial Hose End Timer allows you to set the duration from 2 to 240 minutes. Advanced timer systems can monitor soil moisture levels and turn irrigation on based on your tunnel's needs. You can also adjust the valves on each bed to turn them off or on according to what’s growing. The frequency depends on the time of year, growing region, your plants’ needs, soil type, and the available pressure of your water system.

Hoop House Ventilation

Building active and passive ventilation into your high tunnel is a crucial step that will help regulate temperatures inside, circulate air to keep it fresh and healthy, aid in pollination, and control pests. Size, design, climate, and budget will factor into what type of ventilation you install. Getting expert advice on selecting a system is advised. While you can install mechanisms later, your tunnel will be more efficient and productive immediately if you include them in your initial build. 

Passive ventilation includes vents that allow hot, stale air to escape, sidewalls that rollup to allow fresh air to enter and facilitate cross-ventilation, and windows and doors that open the way you would your windows and doors at home on a nice day for a natural breeze. 

Active ventilation involves exhaust fans that pull out stale air, circulation fans (HAF) that move fresh air around inside, and air exchange systems that involve intake fans or vents to balance the ecosystem. 

Related: Managing a Greenhouse | Regulating Humidity & Temperatures

Layout Planning

Based on the width and length of your tunnel, draw up a map of what you want the beds to look like before getting to work. Many small-scale farmers use a permanent bed system with 30-inch bed spacing and 12 to 18-inch pathways. Streamlining your farm so beds are the same length and width allows you to cut row cover, insect netting, and landscape fabric to the same size, and it will fit anywhere. Some tilthers, broad forks, and rakes are made to fit this system because of its popularity. 

Convert your measurements into inches to make the layout more straightforward. Below is an example of a breakdown using a 30-inch bed system. 

Example: Your tunnel is 30 x 54 feet long, or 360 x 648 inches. Decide how wide you’d like the pathways to be, and add that to the 30-inch width for each bed. Consider leaving some space along each wall for ease of planting and harvesting. 

For a 12-inch pathway: 30-inch bed + 12-inch pathway = 42 inches. 360 / 42 = 8.5.

Create eight 30-inch beds, bringing the two outside beds to the wall. 

For an 18-inch pathway: 30-inch bed + 18-inch pathway = 48 inches. 360 / 48 = 7.5.

Create seven 30-inch beds, leaving a few inches on each edge. 

While you could create six beds with more prominent pathways, this does not utilize the space to its highest potential. 

Leave the extra 4 feet divided into the two ends of the tunnel for walking space and tool storage. While stretching them to the wall might be tempting, you’ll find it much more “lean” or efficient to leave clear routes to tools and doors. The space at the end also allows for weight bag storage when using frost blankets or insect netting on a bed. Check out Ben Hartman’s book The Lean Farm to learn more about incorporating ideas from lean farming on your farm.

Planting and Maintenance

Flower sowing schedules should be an evolving document that changes as you gain experience. 

Planting Guidelines

Vanessa grows flowers in her high tunnel to extend the season and takes advantage of her growing zone’s short winters.

For fall plantings:

• Start biennials and hardy annual seeds for overwintering in August.
• Transplant them mid-October through November 1; think Sweet William, Foxgloves, Bells of Ireland, Iceland poppies, Bachelor’s Buttons, and Larkspur. 
• Vanessa waits until after Christmas to soak ranunculus and anemone corms so their bloom time aligns with the start of their farmers’ market in April. Optionally, you can pre-sprout them in 1020 trays and grow medium after soaking. Utah State University has a comprehensive publication on Ranunculus Cut Flower Production in Utah that’s worth a read. 
• There are several classifications of tulips divided into bloom time. Experiment with planting time and various cultivars to find what works best on your farm. Many growers use the egg carton method by digging down several inches, packing tulip bulbs extremely close, covering them with soil, and mulching them. I also know cut flower growers here in New England who plant them in black crates in their unheated high tunnels, then force them by heating them in the spring. The possibilities are endless; finding what works takes experience and record-keeping. Our, “From Setup to Bloom: Your Step-by-Step Guide to Hydroponic Tulips,” article has some great ideas.

There are some ideal candidates for fall planted overwintering, but be sure to have a market to sell them, as they’ll be ready in late winter or early spring. There is a bit of a difference in bloom time across zones, but generally, you can count on ranunculus, anemones, and tulips blooming three to four months after you plant them. Count backward from the date you want them to bloom and adjust your sowing schedule. Plan to plant corms and bulbs between November and February. 

Pro tip: For easier covering and uncovering, stake short wooden posts in your garden beds and add tennis balls to the tops. The balls protect frost blankets from tearing with the frequent frost blanket movement required in the early season. 

For spring and summer plantings: 

• Use the seed packet as a guideline for when to sow. 
• If you’re to sow four to six weeks before the last frost date, identify your region’s last anticipated frost date, then count four to six weeks back and add that date as the sow date. Add three to four weeks to that date to plan a second succession. 
• Pay attention to requirements like darkness or light to germinate, heat mats, or stratification. 
• Sow tiny seeds in strips or 128-cell trays.
• Step them up when they are an inch or so tall. 4-Cell Plug Tray Inserts or an Air Prune Propagation Tray—72-Cell will work well. 
• Set trays inside the high tunnel instead of outdoors to harden off plants as you usually would. Start five to seven days before transplanting so they can acclimate to the new environment.

Direct sow flower seeds as soon as you can work the soil or as advised on the seed packet. Ensure no weeds are present. Keep the soil moist until germination. Set up drip irrigation lines immediately instead of trying to maneuver lines around young, vulnerable seedlings later. 

Pro tip: Pinch back snapdragons, celosia, marigolds, salvia, zinnias, cosmos, calendula, and rudbeckia when seedlings are two to three inches tall to encourage a bushier growing habit and increased productivity. 

Succession Planting on the Flower Farm 

Whether or not you plant successions depends on the species’ longevity, productivity, and ability to handle the heat. While snaps and cosmos will continue to provide fresh flushes of blooms with regular harvesting, ageratum, cockscomb, and celosia will do best when planted successively a few weeks to a month apart. Plant tubers and bulbs once annually.

The timing between successions depends on the plant type, your growing region, and market demand.

Care and Upkeep

High tunnels offer protection from the elements but also experience extremes as temperatures increase. Monitor soil moisture, temperatures, humidity, and air circulation to keep plants healthy. Invest in a simple moisture meter, temperature sensors, and an EC meter to measure electrical conductivity. Hanna Instruments makes affordable, high-performing tools great for small-scale farmers. 

Annual maintenance of the high tunnel itself is essential. If you ignore minor repairs like plastic tears and gaps that allow cold air to seep in, health and yields will suffer. Also, minor issues will continue to grow; you should deal with them before they become more significant and potentially cost a lot of money to fix. Make a list of items to inspect while preparing for winter to get in the habit of servicing tools and machinery and making repairs. 

Soil Preparation and Fertilization 

Fertilizers should be water-soluble so they are absorbed quickly and efficiently into the soil and immediately available to plants. Since high tunnel soil does not receive precipitation, soluble salts may build up. 

Manage the fertility in your high tunnel differently than in outside beds because there is no precipitation to flush salts out and because there is overall nutrient depletion. Test soil fertility and pH annually to help guide what you amend with and how often. As you gain experience, you’ll learn the signs of nutrient deficiencies and stressors that affect growth, health, and productivity. 

Consider how long your flowers will be in the ground. Like tomatoes or peppers, long-season and overwintered flowers require more fertilization. Work in well-aged manure or compost, but don’t overdo it, as high nitrogen can lead to stress and disease. Plants don’t need fertilization during their dormancy, but you should follow a schedule once new growth appears. 

Use a light deprivation silage tarp before planting to rid the area of weeds and remove debris that could harbor disease. Run fans and vent the high tunnel to keep the air fresh. As planting time gets closer, monitor the temperatures and humidity. Provide as constant and consistent conditions as possible to avoid stress on plants. 

Related: Using Silage Tarp for Organic Weed Control and Bed Prepping

Pest and Disease Management 

Some pests and weeds can transmit dangerous diseases, so know what to look for and how to get rid of them quickly to avoid crop loss. 

Reduce pest pressure by: 

• You can set traps, adopt a barn cat, spread coyote urine, or plug-in deterrents to deter mice and voles. Bulbs and tubers make tasty snacks. 
• Companion planting with herbs and alliums 
• Planting trap crops like Tokyo Bekana and arugula. 
• Attracting natural predators like lacewings, minute pirate bugs, and predatory mites.
• Scouting regularly and squash pests and eggs 
• Harvesting regularly 
• Practicing delayed planting around pest lifecycles 
• Using sticky traps 

Cutworms and slugs are significant pests that cause extreme damage to young seedlings and are common in the spring. Unfortunately, both are nocturnal, so they’re hard to control. Caterpillars, flea beetles, and thrips are also heavy hitters. A University of Illinois Urbana-Champaign Illinois Extension study looked at the effects of aphids, whiteflies, and leafhoppers in high tunnels after they released natural predators with decent results. The key is finding something that doesn’t cost farmers a lot of money and aligns with their growing practices. Contact your local extension office for help building an integrated pest management (IPM) plan in your tunnel.

Reduce the risk of disease by:

• Watering early in the day
• Avoiding overwatering and overhead watering
• Not adding too much nitrogen
• Using a moisture meter to monitor soil moisture levels
• Proper ventilation 
• Wider plant spacing if disease becomes an issue
• Using fungicides preventatively following a schedule 
• Crop rotation 
• Using straw mulch to avoid water splash up
• Managing weeds that serve as hosts for dangerous pathogens
• Providing good drainage and avoiding standing water 
• Keeping tunnels clear of plant debris 
• Proper sanitation of clothing and tools
• Ensuring plants, soil, and compost are disease-free, and consider opting for disease-resistant cultivars. 

High tunnels often provide the perfect warm, humid conditions for spreading diseases quickly. Managing humidity will help reduce the risk of powdery mildew, crown and root rot, and gray mold. Keep levels at 25% to 70%. I cannot stress the importance of proper ventilation when growing in a high tunnel, especially during winter. Opening end walls and ridge vents will allow stale air to exit and fresh air to enter, circulating new air and cooling the space down. 

Pruning

If you practice regular harvesting and deadheading, pruning won’t be necessary. However, prune large, unruly plants to maintain shape and tidiness. Most plants can tolerate losing a third of their size without adverse effects. Prune perennials as advised, removing old or dead wood during dormancy. 

Related: How to Propagate Roses From Cuttings: The Best Way to Grow New Roses From Stem Cuttings

Harvesting and Post-Care of Flowers on the Farm

Harvest early in the morning after the dew has dried up and before the sun becomes hot and blooms open. Give harvest buckets a good wash with dish soap, a splash of household bleach mixed with water, and a sturdy brush. Any bacteria in the bucket will quickly infect your freshly cut flower stems, so this step is imperative for the flowers’ longevity. Rinse the buckets and fill them about ⅓ with fresh water. Grab clean, sharp snips and head out to your fields. 

How To Harvest: 

• Cut low down on the stems to encourage long stems. “Cut long to get long,” Vanessa says.
• Use snips on an angle for maximum hydration surface area.
• Strip the leaves on each stem, which will dirty the water and increase the risk of rot.
• Hold the blooms upside down to avoid damage.
• Harvest until you have eight to ten stems or whatever is comfortable to hold with your non-dominant hand. 
• When your hand is full, turn the stems right-side up and place them into the bucket. 
• Continue harvesting until your bucket is full but not overcrowded. 
• Harvest two to three times a week to encourage fresh blooms and to get blooms before pollination, which decreases their vase life. 

When To Harvest:

While this differs slightly by species, here are a few general rules: 

• Cut anemones before the blooms are fully open, and there is about a half-inch between the bloom and the top leaf collar. If cut too early, they may only partially open. Experiment with timing until you get a feel for it. 
• Since dahlia blooms don’t open much more after harvest, cut them when they’re primarily open but before they dry out or become pest-damaged. Cut low on the stem above a node. Dahlias' thick, hollow stems will soak up lots of water post-harvest.
• Lizzies bloom from the bottom, so harvest them when the lowest bloom is opening, or a cluster of three to four blooms is slightly open. 
• Harvest ranunculus when they’re at a soft marshmallow stage. Some growers say they’ll last longer if you allow them to open and close a few times before harvesting. 
• Snapdragon blooms start at the bottom, but since there are multiple blooms per stem, wait for about a third to be open before harvesting. 
• If your Stock is not a cut-and-come-again flower, so consider planting two successions a few weeks apart for continuous early spring blooms. 
• Harvest Sweet William when ⅓ to ½ of the flowers are open on each stem. Cut to the ground level. Leaves can be a little tricky to strip. 
• Harvest tulips at the “cracked bud” stage when you recognize their mature color and the buds are plump. Leave the top two leaves on for display, but remove the rest. Pro tip: Store them in crates wrapped in paper out of water in a dark, cool place for up to two weeks after harvest. Rehydrate them by snipping the stem end and placing them in fresh water. 

As you gain experience harvesting new varieties of flowers, note how they continue to grow, stem length, bloom period length, storage time in the cooler, and vase life. This data will help shape your future decisions about what flowers are worthy of your high tunnel space. 

Post-Harvest Care and Storage

Experiment with the storage temperature and floral preservation mixed into your harvest water. Vanessa indicated that while she has tried them in the past, they’re expensive, and she didn’t notice enough of a difference to make them worth continuing to use. She does, however, hand out packets of flower food to each customer who purchases bouquets at the farmers’ market. 

Store flowers in a cooler set around 36°F (2°C) away from ripening fruits like melons that may decrease their vase life. Pro tip: Zinnias don’t love cold temperatures, even after harvest. Keep them out of the cooler for short-term storage, away from direct sun and heat, as long as you use them within a day or two. 

Related: How to Grow Sunflowers For Cut Flowers with Vail Family Farm

FAQs

What are the best flowers for beginners to grow in high tunnels?

Snapdragons, stock, sunflowers, marigolds, and feverfew are forgiving flowers to plant and care for. Beginners can successfully grow these and gain the confidence they need when transitioning to more challenging flowers.

How do high tunnels extend the growing season for cut flowers?

Protection from inclement weather patterns and frost allows growers to start seeds, transplant seedlings earlier, and grow later into the fall. Controlling the conditions, water, and humidity increases overall health and production. Being the first to market will create demand, and producing late-season blooms will increase profits. 

Can you grow cut flowers in a high tunnel year-round?

In certain regions, yes, high tunnels can produce cut flowers year-round. With experience and proper soil and fertility upkeep, your high tunnel can grow flowers well beyond their traditional seasons, allowing you to charge more for highly demanded products in the “off-season.” Consider growing cold-hardy edible flowers in the shoulder season to boost income. 

What are the initial costs of setting up a high tunnel?

The cost of high tunnels varies greatly depending on production, the materials used, their size, and additional components like wind bracing, end walls, gothic-style bows, etc. Growers should consider site work, drainage, power, heat, labor costs, and any material needed, like topsoil or drainage stones. 

Depending on the dimensions, accessories, and size selected, you should expect to spend between $5 and $12 per square foot. 

How does climate affect the choice of flowers for high tunnels?

Climate is a significant factor to consider when selecting flowers. Select flowers that thrive in your local conditions instead of pushing the boundaries of your growing zone. Overwintered and spring-planted sweet peas may do great in Vermont but will peter out when temperatures spike in early May. Learn about successful cool-weather techniques for producing hardy annuals in  Lisa Mason Ziegler’s Cool Flowers, no tunnel heating required! 

Knowing the limits of your growing zone is essential. You’ll learn what thrives in your high tunnel by experimenting and collecting good data. 

Written by Jenna Rich of Partners’ Gardens LLC.