· by Michael Blair, Nashville's Landscapers
April is when garden centers are full and when most planting happens here. It is also close to the worst time to put a tree or shrub in the ground in Middle Tennessee, because it gives the root system about eight weeks before it has to survive a Nashville summer.
Why autumn wins for woody plants
Soil here stays warm well into November while air temperature drops. That combination is ideal: roots keep growing in warm soil while the top of the plant is dormant and demanding nothing.
A tree planted in October has all winter and all spring to establish before its first summer. The same tree planted in April has weeks.
What each type wants
Trees and shrubs: October through early December is the strongest window here, with late winter a reasonable second. Avoid planting into frozen or saturated ground.
Perennials: spring and early autumn both work, with autumn slightly better for anything that resents summer heat. Warm-season grasses are the exception and genuinely prefer spring, because they need warm soil to root at all.
- Trees and shrubs: October to early December
- Perennials: September to October, or April
- Warm-season grasses: April to May
- Cool-season turf seed: mid-September to mid-October
- Bulbs: October to November, before hard ground
The watering obligation nobody mentions
Autumn planting does not remove the need to water. A newly planted tree needs regular deep watering through its first full year, including dry spells in winter, because it has not yet reached beyond its original root ball.
The common failure here is watering diligently for six weeks and then stopping. The second summer is when an under-established tree gives up, which makes the cause hard to see.
What not to plant in high summer
Almost anything woody. July and August planting in Middle Tennessee means a plant that has to grow roots in hot dry clay while supporting a full canopy, which is the hardest possible ask.
If a plant has to go in during summer, plant in the evening, water deeply and immediately, mulch, and accept that it needs watching twice a week rather than weekly for the first two months.