The delicate and fragrant magnolia flowers -- in hues of white, pink, fuchsia and yellow -- offer early spring cheer. While many think of these trees as southern plants, notes John Eustice, a Minnesota horticulturist, gardeners can plant these trees as far north as hardiness zone 4. This wide geographic range affects planting time for these trees.
When you plant your magnolia tree depends largely on where you live and the type of tree you have. Evergreen magnolias including the southern magnolia and sweetbay magnolia do well when planted in the spring. Deciduous magnolias can be planted in either the fall or the spring. The United States National Arboretum recommends spring planting of deciduous magnolias for gardeners in the northern United States and fall planting for gardeners in the southern states. Southern gardeners can plant these trees at any time of year.
To help your tree adapt, dig a wide planting hole that is twice as wide and deep as the tree's root ball and loosen the soil at the bottom by jabbing your shovel against the earth. Remove the tree from its container, then place the magnolia tree in the hole so the trunk is vertically straight. Check that the tree is planted only as deep as it was planted in the container -- there will be a visible soil line on the trunk -- and fill in the hole with dirt. After planting, water to compact the soil around the tree's trunk.
Magnolia trees benefit from wind protection, since strong gusts can blow off their lovely flowers. Choose a suitable full sun location that offers some shelter from wind. The University of Minnesota advises against planting balled and burlapped or bare-root magnolia trees: the tree's sensitive root system dislikes the disturbance associated with these forms of planting. Containers put less stress on the tree's rope-like roots.
Most magnolia trees can grow in United States Department of Agriculture hardiness zones 4 to 8; some are only hardy to zone 7, while others extend into zone 9. This territory covers a wide swath of land with different climates. To have success with this tree, choose a cultivar adapted to your area and plant it in full sun. Northern gardeners should stick to spring planting so magnolias get over transplant shock before the cold winter arrives, while southern gardeners have more flexibility due to milder winters. In general, magnolias -- especially the southern magnolia -- have a rough adjustment period to planting no matter when planted.