It’s no secret that beaver and nutria can decimate riparian tree plantings. Young seedling and sapling trees with tender bark are no match for powerful beaver and nutria teeth and jaws. Choose SunFlex to keep your seedling trees growing fast, straight and strong in the riparian zone where beaver and nutria live.
Deer Browse Alert: 4½ ft tall (and shorter) grow tubes, tree tubes and tree-shelters of any kind do not protect against deer browse above the height of the tube – period! If deer are in you area choose either the 71-inch Buck Shield™ or 58-inch Doe Shield™ SunFlex Grow Tube System.
Deer are unquestionably the number one threat to nearly all wild-land and many urban tree plantings. In fact, when you’re planting in “deer country” SunFlex may be the only hope a young seedling has. White-tailed deer, with an average height of 36-40 inches at the shoulder plus its neck and head length, can easily browse most any unprotected tree below a height of about 4½ ft tall.
Trying to grow unprotected hardwood seedlings in deer country is usually futile. Unprotected seedlings stand no chance against hungry mouths – see image on right showing the all-too-familiar fate of an unprotected seedling repeatedly browsed and unable to grow-up to escape deer and other critters.
Using shorter tube shelters less than about 4½ ft tall is also of little use as these tube heights expose the emerging tree right at, or close to the feeding level for most North American deer species. Once deer munch the top of the emerging tree its natural form is irreparably harmed. The tree usually responds by robbing its root system to replace lost growth in multiple stems in an often futile effort to grow past the deer. The solution needed here is a real grow tube that’s up to the challenge of protecting and growing your trees safely above the browse line. The 71-in tall SunFlex Buck Shield or 59-in tall SunFlex Doe Shield Grow Tubes get the job done the first time, every time.

The before and after images below show how easy it is for deer to browse seedlings that emerge from the top of shorter tubes (35-in tube shown below). The lesson here is, don’t waste money trying to save money on tubes too short for the animal threat in your area. Instead, choose a Plantra grow tube tall enough to get the job done right the first time you plant. Don’t let deer make a meal out of your seedlings. Choose the SunFlex “Buck Shield” or “Doe Shield” Grow Tubes to grow your trees past the deer!

Before & After – Night-time raid by whitetail deer on 35-in. tube caught on trail cam demonstrates
the need for taller (59-in minimum or 71-in preferred) grow tube shelters in deer country.
What Is The SunFlex System?
SunFlex is the only integrated grow tube system ever designed to grow your seedlings taller, straighter, and bigger – all in record time the way professional nurseries do! Only SunFlex combines superior grow tube design which works like a mini-greenhouse with super strong, rot-proof Trunk-Builder™ stakes that support and flex to build stem strength. The SunFlex System is the “growers choice” to get hardwood seedlings Survive, Thrive and Succeed, the first time, every time.
Born in a greenhouse, SunFlex wins the battle for seedling establishment in your field, yard or open space! SunFlex combines superior seedling protection and greenhouse growth benefits with trunk-building flexibility of a rugged, reinforced fiberglass support stake. Together, they grow your seedlings “naturally” inside a mini-greenhouse that “moves” with the wind to promote accelerated but balanced growth both inside and outside the grow tube.
Why Should SunFlex Matter To You?
That’s simple. Trees grown inside SunFlex have the highest survival rates and healthy, balanced growth from roots to shoots all to make your planting a success the first time, every time! The key to the SunFlex System is its unique ability to grow the seedling “naturally” inside its state-of-the-science greenhouse that “moves” with the wind to promote accelerated and balanced growth. Traditional tree tubes and tree-shelters do not optimize PAR sunlight and rely on old-tech, rigid staking systems (made of oak, wooden lath, metal and bamboo) that inhibit natural stem growth and strength. SunFlex, on the other hand, protects and grows! By promoting optimal growth inside and outside the grow tube you might say that SunFlex plays below and above the tube rim!
The SunFlex Seedling System works for you and your hardwood seedlings two growth-maximizing and money-saving ways:
1. Faster, balanced growth from advanced SunFlex greenhouse technology means bigger, healthier trees…..faster!
- SunFlex protects and “grows your seedlings from roots to shoots with advanced greenhouse technology that assures your seedlings survive against the many threats that can kill them in their first seasons. Seedlings often lose 75% (or more!) of their potential growth due to the impacts of environment stress caused by wind, animals and physical damage. To combat this loss, SunFlex optimizes the “Big 4” (Sunlight, CO2, Moisture & Temperature) to maximize your tree’s potential and funnel it into growth instead of just survival. With SunFlex, the need to replant over and over because of wind desiccation or animal browse will be over…for good!
- Unlike traditional tree tubes and tree shelters, SunFlex Grow Tubes are twin-walled for superior light diffusion and translucent to growth-optimizing sunlight trees and shrubs need. SunFlex is packed with advanced greenhouse technology to stimulate phytochrome to grow the whole plant from roots to shoots necessary to get your new seedlings off and running with the sun. And unlike products with different diameters, SunFlex grow tubes have a uniform diameter so all of your trees get the same great growth maximizing benefits, not just some of them. After all, we believe every tree should count!
- In addition to providing superior greenhouse benefits, the entire SunFlex series is engineered with Plantra’s exclusive “Cross-Flow” venting to promote effective air movement. Cross-Flow increases CO2 replenishment, reduces excessive moisture buildup and promotes proper dormancy (hardening off) before winter, even in the coldest regions.
2. Trunk-Building strength, ease of use and long field life are engineered into every Trunk-Builder™ support stake.
- The only way to grow the best tree is to grow the whole tree and that includes the main stem. Plantra’s Trunk-Builder Stake (patent pending) is the only “purpose-built” grow tube shelter support stake engineered with trunk-building flexibility and strength to grow bigger, healthy stems and roots. Like everything we do at Plantra, it all begins with growing the plant and Trunk-Builder is no exception. Trees use a variety of environmental influences to grow and wind is an important factor in normal stem development.Trunk-Builder stakes harness the wind to stimulate plant growth responses that encourage stronger stems – a process known as “thigmomorpogenesis.” Unlike traditional, rigid staking systems which can lock tubes in place and prevent natural movement of the developing tree trunk, Trunk-Builder gently moves back and forth when the wind blows and returns to straight to train your trees tall, straight and strong.