A volunteer sorts prairie seeds collected at the Arboretum for future restoration projects. Photo: Bryce Richter/UW–Madison

A volunteer sorts prairie seeds collected at the Arboretum for future restoration projects. Photo: Bryce Richter/UW–Madison

Garden Care By Season

Maintaining healthy Arboretum gardens takes year-round care. Many tasks are similar for the horticultural collections (Longenecker and Viburnum gardens) and the native plant garden, but there are, naturally, differences as well.

In winter, we complete dormant season pruning outdoors, and in the greenhouse we sow seeds in flats. We transplant young plants into pots or plugs when they are large enough.

As spring approaches, after danger of frost is past, we transfer trays of young plants outdoors to the nurseries to harden off (acclimate) so they can be planted in gardens and restorations. In Longenecker Gardens, we remove cages and screens that protect specimens from deer in winter. In the Native Plant Garden, we trim back last season’s growth from garden beds.

As soils thaw and warm, planting begins. We transplant trees and shrubs from the nursery to the gardens, plant bare root materials into pots, the nursery, or directly into the garden, and begin planting potted herbaceous perennials. We weed the plant nursery. We maintain plants in the nursery by transplanting them into larger pots or pruning roots and adding soil to keep plants in the same sized pots.

New tree and shrub plantings (marked with blue flagging in the field) may require watering if we do not receive 1” of rain per week. We use irrigation sprinklers or a truck with a water tank to reach specimens in the collection. Herbaceous plants in the Native Plant Garden are watered thoroughly on planting day and mulched lightly. They rarely need supplementary watering after that.

During the growing season, from April through October, we weed Native Plant Garden beds using hand tools. In Longenecker, in addition to hand weeding, we may use herbicide to reduce weeds as well. We often spread wood chip mulch around trees and shrubs to maintain even moisture in the root zone, protect the trunk from mowers, and give an attractive appearance. We mow lawn areas, which are not treated with herbicide or insecticide.

Our gardeners continually monitor planted areas for growth and health, beneficial or harmful insects, damage, wildlife, invasive species, fruit and seed set, and change in garden composition over time.

We can still plant perennials during the fall. In the native plant garden we collect seeds from grasses and late-blooming forbs. We fence woody evergreen specimens in Longenecker to prevent animal browse during winter. Fallen leaves are used for mulch or mowed over so that they do not smother lawn areas.

Along with the outdoor pruning and greenhouse tasks, winter is a busy time indoors. We write garden reports, order plants and seeds, do research and teaching, celebrate our volunteers, hire students, schedule volunteer gardening sessions—and look forward to spring.

Gardening at the Arboretum

Students and community volunteers work side-by-side with Arboretum staff in garden care. We accomplish important seasonal tasks while learning together. Garden volunteers learn about plant identification, planting techniques, weed identification, effective weed control methods, pruning, garden ecology, and natural history.