Welcome to Gardening 208! In this “course” we cover the basics of gardening in Idaho and try to answer any questions surrounding the topic. As the season goes on we will focus on more specialized areas of gardening. For now, here is an introduction to Franz Witte’s Garden Center and how seasons and weather directly influence plant shipments, orders, and stock.
Open Year Round
Franz Witte Garden Center never officially closes for the season. As our growing season winds down, we present a strong fall and holiday offering. Inclusive of gifts, home decor, and live goods. We remain open through the winter months, carrying stock in house plants, pottery, and bulk materials. Long lasting perennials in the Treasure Valley are generally done by the first frost which historically takes place in mid-October. Trees and shrubs go dormant in our climate by mid-fall after the leaves put on a stunning showcase. This is typically when the garden center stops receiving orders for deciduous plant material. Evergreens and other trees and shrubs with winter interest are sold in November and December, along with evergreen bundles.
Seasons and Shipments
We get a lot of questions about when specific plants will be in for the season. Knowing the exact dates that our plant material will arrive is difficult, even two months in advance. For example, we order trees about four to six months ahead of time. Growing and shipments are highly dependent on weather because we order from various growers around the United States. Weather patterns vary year to year, which directly correlates to plant growing habits. Some of our growers and suppliers are based out of California and Oregon which have different climates and weather than Idaho. Listed below are general time frames when we receive our first shipments for the season.
End of February to beginning of March
- Spring flowering trees and shrubs: Still dormant at this point. We want them to adapt to our climate, otherwise they will lose their blooms.
Beginning of March to April
- Deciduous trees
- Summer flowering shrubs
- Cool season annuals: Pansies, primroses, etc.
Beginning of March to April
- Ornamental Grasses
- Warm season annuals: Petunias, verbena, sweet potato vine, coleus, etc.
- Vegetable Starts
The first week of May leading up to Mother’s Day is when the garden center is fully stocked and has the biggest selection. We continuously order throughout the season to keep our inventory fresh and stocked.
Planting at the right time in Idaho is vital to the success of a plant’s lifespan. The Treasure Valley is a zone six on the USDA hardiness scale. The USDA Hardiness Zone Map separates planting zones by 10 degree increments based on a climate’s average annual minimum temperature. Knowing the zone you live in is important to compare garden climates with the climate where a plant is known to grow well. If there is a plant you want to survive and grow for years in your landscape, then it must be tolerant of year-round conditions. That is why certain plants do not grow here if you moved from out of state. Our Boise plant nursery carries stock appropriate for the Treasure Valley’s zone, and our McCall location has an inventory more suitable for northern climates.
Trees, Shrubs & Perennials
The Treasure Valley is high desert with hot, dry summer temperatures that support the growth of warm-season plants. Spring and fall reduce the growing season with frosts, and cold winter temperatures may damage or kill many trees, shrubs, and perennials not suited for the climate.
Spring and fall are ideal to plant trees, shrubs, and perennials. Spring is recommended because growing conditions are in the plant’s favor: extended day lengths, moisture in the form of rain, and increasing temperatures. Plant energy in the spring goes into foliage, flower and branch development. Fall is also recommended because above ground growth slows and energy is put into root development — allowing deep, strong roots for the next season. Keep in mind that plants are under stress when they are moved or replanted until they can establish in their new location, so ample conditions are important for the success of your plant.
Summer is a fine time to plant in our area, but be aware of hot temperatures. Water is a huge factor when planting, especially in the heat of the summer. New plants get all their moisture from a very small amount of roots until they can establish. It is important to never let a root ball dry out when freshly planted.
Vegetables & Annuals
The Treasure Valley is great for vegetable gardening because you can get the most out of your land with cool and warm season crops. Cool-season crops grow best in 50°-75°F temperatures while warm-season crops grow best in 70°-85°F temperatures. Knowing the frost dates for your region is important for the success of your garden. The Farmer’s Almanac is a great resource for finding your frost days. Cool-season crops can handle light frost while warm-season crops cannot. This information allows you to refine your planning and purchasing for proper seeds or starts. Check out this University of Idaho Extension Spring Vegetable Planting Guide.
Annuals are treated similarly to vegetables. Cool-season annuals and warm-season annuals are perfect for shifting seasons. Annuals add fresh and bold color to the landscape as they can be changed out multiple times throughout the season. Our garden center sells annuals periodically through the season that thrive in the Treasure Valley’s temperatures.
Bring Your Questions
We love Idaho and we love gardening here. Whether it be outdoor landscapes, pot designs, front yard gardens, interior ‘plantscaping’, vegetable gardens, or anything in between, our staff is willing and happy to answer your questions. Hopefully this little introduction to gardening in Idaho opens a door of curiosity and encourages you to get outside. Our climate and seasons offer a diverse landscape unique to the United States. Be on the lookout for more Gardening 208 topics throughout the season where more plant questions will be answered!
By Riley Rehberg