Your forsythia in summer turns into a dense green shrub with oval leaves and no flowers. You won't see any color from this plant during warm months. The forsythia summer foliage is plain and green, but it does give you a thick screen of leaves that blocks views and wind.
I was surprised by how fast this shift happens in my own yard. One week my forsythia was covered in golden yellow flowers that lit up the whole front bed. Then within 2 to 3 weeks every petal dropped and I was staring at a big green bush. The forsythia after blooming phase caught me off guard the first year I grew one. Nobody had warned me about the plain summer look.
The forsythia green leaves have their own quiet charm if you look at them up close. Each leaf is oval shaped and about 2 to 5 inches long with a serrated edge. The leaves grow thick along arching branches and make a solid wall of green. You get good privacy from this plant even without the flowers showing.
Here's what your forsythia looks like through each season so you can plan your garden around it. Yellow flowers cover bare branches in early spring. By late April the blooms fade and fresh green leaves take over. That green color holds steady all through summer. In autumn your leaves shift to a yellowish green tone before dropping in late fall.
Wisconsin Extension notes that forsythia is one of the last shrubs to drop its leaves in fall. This means you get green screening from your plant longer than most flowering shrubs in your yard. While your hydrangeas and spireas go bare, your forsythia keeps its leaves up for a few more weeks.
Since your forsythia brings zero flower color during summer, you should plant companions that pick up the slack. Bluebeard blooms blue from July through September right in front of your forsythia. Spirea adds pink or white flowers in early summer. Weigela fills the gap with red or pink blooms from late spring into midsummer. I planted all three around my forsythia and now I get rolling color from March all the way through October.
Think of your forsythia as a green backdrop during the warm months. Black-eyed Susans, coneflowers, and daylilies all pop against that dark green wall of leaves. Your forsythia plays a supporting role in summer so your other plants can shine. Then it takes center stage again next spring with another burst of golden yellow flowers that steal the whole show.
Read the full article: Forsythia Bush: Complete Growing Guide
