The Hort Report: Start saving seeds from annual, perennial flowers that have finished flowering this year

The first day of fall was Sept. 22. The daylight hours are getting shorter. You have less time to work in your garden, flowerbeds and yard after 5 p.m. I enjoy this time of year and always find things to do every day. 

The weather has been hot and dry for the past several weeks. Seems like 2023 all over again.

Rain will help to seal cracks in the yard. If we don’t get the cracks sealed, the cold air this winter will get into the root systems and cause many perennial plants, flowers, trees, shrubs and bushes to die during a hard, cold winter.    

Many annual and perennial flowers have finished flowering for this year. You should start to save seeds from some of these flowers. I plan on collecting some flower seed heads from them once they turn brown and dry to the touch. 

I will collect several different types of flower seeds, putting the seeds in separate brown paper bags. Plastic bags might cause moisture to build up in them.

Put the bags in a sealed glass container to keep out air and moisture. Store them in a cool dry place until the time to plant them in the spring of 2025, making sure to label the bags.  

Now is a good time to divide flowering perennials. Some of the most common types of perennials to divide are daylilies, bearded irises, peonies, bee balm, columbine, summer phlox, catmint, and hollyhocks. Try to divide your perennials every three years. Make sure to divide them at least four to six weeks before the ground freezes.

When you divide perennials this time of year, they will have time to be planted in another flowerbed this fall, allowing them to start to grow roots and make it through the winter. 

Once you divide them, be sure to get loose soil around the roots of the perennials. I will sometimes put some organic matter into the hole that I made for them to go in. I will mix it with soil from the hole. Once the roots are covered, I will water them in, add more soil and finish watering the soil around the roots. I do this for both the hole the parent perennial plant is in and the hole I’m putting the divided perennial plant part into. 

Don’t prune the perennial flowers you are transplanting this time of year. You want them to put all their energy into the root system and store up food for the coming winter. 

Once you have moved, divide your perennials. You can look at pruning them in a few weeks. You want to hold off pruning them until a couple of hard freezes. They are using their leaves to photosynthesize and store energy to survive the winter. If you prune them now, they may start next spring weak and spindly.

I will then prune them and use the pruned leaves and other plant parts as mulch to help protect the plant roots from a hard cold winter. Laura and I will sometimes take the seed heads of the flowers and sow them on top of the soil in the flowerbeds, not waiting to save them over the winter. 

Don’t prune fruit trees now unless you are pruning broken, damaged or diseased limbs and branches. Wait until the first hard killing freeze.

I appreciate your questions in the past and look forward to them in the future. Please call me at 573-588-2040 at Shelby County Implement in Shelbina, Mo., email me at sci63468@hotmail.com or contact me on Facebook at Greenwell’s Greenhouse Group. Come and see me or stop me anytime. I enjoy visiting with people. Your questions help me learn more, too. 

Enjoy a great garden harvest.

Pat Greenwell is the owner of Shelby County Implement in Shelbina, Mo. He was a high school agriculture teacher for 11 years. He has taught adult vocational agriculture since 1987. He also is a research assistant at the Truman State University Ag Department Farm.