As autumn arrives in Minnesota, the Minnesota Landscape Arboretum showcases its iconic pumpkin tree, a striking 12-foot display that has become a seasonal favorite. This awe-inspiring presentation has its roots in a project that began 17 years ago. The growers, John and Jenny Thull, Horticultural Research Center (HRC) staff, initially focused on growing squash and pumpkins for the Apple House located near the Minnesota Landscape Arboretum. However, as the idea of the pumpkin tree blossomed, it quickly became a beloved tradition, with themes selected annually to delight visitors. This year, the theme is Oktoberfest, honoring a late friend of John’s, known for his lively spirit and special connection to Germany. The design features an array of blue and white pumpkins, embodying a traditional Bavarian style.
A Diverse Collection
What truly makes the pumpkin tree unique is its astounding variety. This year alone, the Thulls planted and harvested 450 varieties of pumpkins and squash, an astonishing achievement given a very difficult growing season. Dozens of new varieties are added to the lineup each year. The corn cob pumpkin, resembling the oblong corn shape with kernels, has generated excitement this season, alongside a variety of vibrant yellow pumpkins like Lemonade and Mellow Yellow. “Yellow is the new orange,” Jenny notes, highlighting the shifting preferences of customers at the Apple House.
The diversity is not only a visual treat for visitors, but an opportunity to expose customers at the Apple House to lesser-known varieties of squash and pumpkin. The Thulls are focused on exciting and educating customers about the culinary potential of these cucurbits beyond the traditional varieties found at the local supermarket.
Crafting the Pumpkin Tree
The journey to create the stunning pumpkin tree begins months in advance. Seed ordering kicks off in December, with planting starting in May. Given the tricky weather this year, planting took longer than usual, pushing into July. To keep track of their diverse collection, all seeds are organized and planted alphabetically, with handwritten records maintained by Jenny. Once the pumpkins and squash are ready for harvest, HRC staff, Arboretum staff, and a dedicated team of volunteers work hard to carefully transport them from the fields to the HRC for distribution to the Apple House and selection for the pumpkin tree. “It's at this point that we discover if we’re able to pull off our originally planned theme. Some years mother nature has other plans for our color scheme and certain varieties of pumpkin do better than others,” says Jenny. Assembling the pumpkin tree is a labor of love. Several hundred pumpkins are hand selected by the Thulls and arranged to fill the 12-foot structure, with Jenny and her husband John collaborating closely to ensure the aesthetic aligns with their annual theme. “It’s a fun and creative challenge each year,” Jenny reflects. After the tree is completed, the remaining pumpkins find their new home either at the Apple House where customers can purchase them or as decoration at the Minnesota Landscape Arboretum.
Overcoming Challenges
Growing such a wide variety of pumpkins isn't without its challenges. This year's weather posed significant hurdles; excessive rainfall led to oversaturated soil, causing the initial seeds planted to struggle. However, by staggering their planting schedule, the Thulls achieved greater success with later plantings. “This year has been particularly tough,” says John. “We faced a lot of rain in the spring, which hindered the growth of our first seeds. Thankfully, our staggered approach allowed later plantings to thrive.” Despite the saturated soil conditions turning nearly cement-like in the spring, Jenny and John persevered, and at times had to surrender to the force of mother nature.
In addition to difficult weather conditions, crows and other pests were particularly problematic for the pumpkin patch this year as well. According to John and Jenny, when managing 4.5 acres, it’s not physically possible to have a large enough presence in the field around the clock to protect their crops from pests like birds and squirrels. Given the unpredictable nature of weather and wildlife behavior, some elements of crop protection are beyond their personal control. The determination of these growers shines through in their ability to adapt and thrive despite pest and weather difficulties, all while maintaining the quality and health of their crops. Jenny’s little trick in her home garden involves sprinkling hot pepper powder on and around her pumpkins to keep the squirrels away.
Reflecting on the Season
As the pumpkin tree continues to grow in popularity, it represents more than just a seasonal display; it embodies creativity, grit, and the joy of sharing new pumpkin and squash varieties with the public. With each year, John and Jenny cultivate not just pumpkins, but also their growing and planning expertise for years to come.