Why You Should be Trellising Your Crops

Trellising is vital for growing vining plants like morning glory and clematis, indeterminate crops like tomatoes and cucumbers, and top-heavy flowers like lisianthus. Types include vertical, arched, a-frame, and horizontal trellis netting. The type of trellis system you’ll want to use depends on your growing setup, high tunnel height, and the crops growing.  

Types of Trellises

Photo by [Soil and Margaritas]

Vertical Trellises

These are highly advised for climbing plants that grow to 10+ feet, such as indeterminate tomatoes, cucumbers, and snap peas. Vertical trellising saves space and keeps foliage off the ground, keeping plants safe from pests and potential soil-borne diseases. 

Photo by [Lisa Knoebel Photography]

Arched trellises

Use arched trellises to save space when growing vining tomatoes, melons, pole beans, winter squash, cucumbers, and nasturtiums. Create a beautiful vibe for any farm or backyard garden with arches full of ripening seasonal fruit. 

A-frame trellises

A-frames are in the shape of a capital letter ‘A’ formed by two panels that meet at the top. Plants grow from the base of each and grab onto the sides with reaching tendrils, or growers train them up, creating a canopy for anything growing below. 

Trellis Netting

Trellis netting is typically made from durable polypropylene and comes in various heights. Growers can position it vertically or horizontally and hold it in place with stakes or posts. 

This article from the University of Madison Extension Office shows more options for vertical trellis structures. 

Materials Needed

Trellis Framework 

• Farmers growing in beds 50+ feet should consider using metal t-posts to support indeterminate crops grown in fields. 
• Use wooden stakes, bamboo stakes, or fiberglass poles to secure horizontal trellis netting for flowers or determinate tomatoes and peppers supported with the Florida weave method.

Ties 

Velcro® strips, zip-ties, and garden clips hold vertical trellising in place. Climbing plants will attach themselves to the netting with their tendrils. As plants grow, add ties as needed. 

Trellis Netting 

Bootstrap Farmer’s 6-inch trellis netting is made of UV-stable, chemical-resistant polypropylene mesh and is available in 3’, 4’, and 6’ widths. Trellis netting comes in rolls that you can easily cut to the length of your beds. It can be used vertically attached to stakes or T-posts to support pole beans and snap peas or horizontally to support zinnias, cosmos, and snapdragons.

For something more substantial when growing melons or small watermelons, attach cattle panels to T-posts. 

Clips and Hooks

Farmers commonly use clips and hooks to trellis large quantities of high-value crops like tomatoes, snap peas, and cucumbers. It involves a high tunnel system, hanging tomato roller hooks on supports, dropping trellis lines down, and clipping the stems of plants to the line with vine clips.

Related: Building Trellis for Indeterminate Tomatoes 

Step-by-Step Guide to Attach Plants to a Trellis

Preparation

For high tunnel growers, ensure you have enough support to hold the weight of your mature plants. If you’re new to trellising in a high tunnel, check out our complete trellising system. Contact us with any questions about our customizable high tunnel kits or other products. 

Selecting a suitable trellis for your plant

• Consider the weight of the mature fruits of each crop. Tomatoes will require much more weight capacity than lisianthus. For example, farmers should use hooks and clips with tunnel-grown tomatoes, T-posts with tomato twine for field-grown tomatoes, and horizontal trellis netting with stakes for lisanthus. 
• Can the trellis system withstand the entire season? 
• Consider the location and access to sunlight.
• Ensure all the materials used are weather-proof.
• Are your crops vining, determinate, or indeterminate? 

To avoid damage, allow plants to become established before trellising with rollers and clips unless they are substantial at transplant. If using A-frames or arched supports, plant crops at the base or underneath and train them to the trellis as they grow. Ideally, the trellises should be in place before planting.

Pro tip: Plants with a climbing growth habit will search for anything to latch onto, including nearby plants. Gently coax them onto the trellis without tearing their tendrils. 

Methods for Securing Plants

Using Garden Twine or String

When using twine or string to tie plants up, the key is to be gentle but firm. Hold enough tension so the plant can withstand wind and grow straight but delicate enough so you don’t damage it. 

When trellising from an overhead system, you can tie the string directly above or drape a string over the top of the support system and clip both strings around your plant. This method doesn’t require any fancy knots or clips. 

Advantages

• Easily accessible and inexpensive
• Quick and easy to work with 
• It’s a simple way to aid the direction of plant growth 

Disadvantages

• It can be finicky to work with. 
• Strings can cause severe damage if caught up in lawnmowers and other machinery. 
• Can become tangled easily

Using Clips and Hooks

The essential features of any hook system are the weight capability, reusability, cost of replacement spools, and UV resistance. Bootstrap Farmer’s roller hooks contain 100 feet of twine per spool, and our vine clips have a quick-release feature that allows farmers to work quickly. 

The tomato roller hooks hang on the trellis support system above your plants. Provide one hook above plants with single leaders and two for double leader plants. Vine clips are designed to work with roller hook string.

To attach clips to your plants

• Find the sturdiest leaf about 6 inches from the soil surface. 
• Pull the string a few inches below where you want to secure the string to the plant stem. The extra slack will help hold the string's tension. 
• Hold the string taut against the stem and open the clip just slightly above the leaf.
• Secure the string in the clip’s grip and close it around the stem underneath the leaf. Once you secure the clip, the tension will tighten, creating a secure trellis. 
• Repeat weekly or as needed. 

Pro tip: If you see a plant that needs a clip but you don’t have one, give it a gentle twist around the string to tide it over. Only do this in warmer weather when the stem is pliable to avoid damage. 

Using clips and hooks allows growers to utilize the lower-and-lean method. This method will enable crops to grow to their full potential and produce higher, healthier yields. 

Related: Using the Lower and Lean Method for Indeterminate Tomatoes in a Hoop House

Using Trellis Netting

Have a partner help you with this to ensure the netting remains taut. 

For vertical trellis netting:

• Install vertical netting by pounding T-posts or stakes at each end of your crop row and every 5 to 10 feet in between. 
• For stability, you’ll want your posts pounded about a foot into the ground, so keep that in mind when selecting a height. Use Velcro ®, zip-ties, or clips to secure the netting to the posts, tightening the netting to each post so birds cannot get caught.
  Pro tip: Secure the netting as high up on your support posts as possible. Run a line or two of twine near the soil surface to provide enough for beans, peas, and cucumbers to grab onto before heavy fruit is present. 

For horizontal trellis netting:

• Install horizontal netting when plants are small and before blooming begins. They’ll find a square to poke through as they grow, seamlessly creating even airflow and access to sunlight while receiving stability to withstand the weather. 
• Pound a stake in one corner at the end of the bed and slip the netting over the stake.
• Slip a second stake through a square on the other side of the bed that causes the netting to pull tight, then pound it in. 
• Repeat this down the bed, adjusting as needed. 
• If plants are already in bloom, guide them through the nearest square, taking care not to damage or break off the flower tip. For more information, read our article, How to Install Plastic Trellis Netting for Flowers. 

Regular Maintenance

Each time you harvest, prune, or go on a farm walk, note lines that need tightening, slipped zip-ties, or plants that need securing. Train new growth up your trellis system weekly to continue healthy growth. Scout for signs of disease at this time. 

As your plants grow, regular pruning is crucial to overall health. Look near the bottom of the plant. If there are yellowing or brown leaves, remove them. As you harvest, remove all stems and leaves so the plant can focus its energy on producing flowers and ripening fruits. 

Check out our Hoop House Trellis Spring Maintenance video to learn how to keep your vertical trellis system working at peak performance. 

Tips for Success

Best Practices for Tying and Supporting Plants

• Begin tying up plants after they’ve spent a week or more in the ground. Stems are very delicate when plants are young, so it’s best to touch them as little as possible. 
• If stems begin to bend, it’s time to tie them up. 
• No matter the type of trellis you choose, weekly check-ins are advised to add more ties or clips. 
• Be prepared for the weight your plants will create when the fruit matures. 

This article on How to Build a Hoop House Trellis for Indeterminate Tomatoes helps to calculate the expected weight-bearing needs of your trellis system. 

Common Mistakes to Avoid

• Under-preparing for the weight of mature fruits on the vine 
• Selecting the wrong type of trellis for your crops
• Failure to check in and make adjustments
• Not continuing to walk your crops and continue trellising all season

Seasonal Considerations

Remove your trellising system during the off-season. Sanitize and store all parts properly when they’re not in use to extend their life and prevent disease from spreading. 

Frequently Asked Questions (FAQs)

How do you attach plants to a trellis without damaging them?

Be gentle with stems, mainly when plants are still young and small. 

What types of plants need a trellis?

Vining tomatoes and cucumbers, climbing flowers like nasturtium and sweet peas, eggplant, peppers, melons, winter squash, and many annual flowers will perform best when trellised. 

Can I use trellis netting for all types of plants?

Yes, position it horizontally for most flowers and vertically with tall vining plants. 

How often should I check and adjust my plants on the trellis?

Tie this chore into your weekly farm walks or add it to a weekly to-do list so it isn’t overlooked. Most slippage happens at the beginning of the season when plant stability is crucial to their success. 

What is the best material for tying plants to a trellis?

Many home gardeners use strips of old T-shirts to tie plants to support poles. But if you’re growing on a larger scale, we recommend using professional products designed to last season after season and hold the weight of your flowers, fruits, and vegetables. You can also use jute twine, zip ties, vine clips, or cotton string. 

Written by Jenna Rich of Partners’ Gardens LLC