Fall time is a wonderful time to be in the garden ; the air is cool, the ground is (sometimes) dry, and weeds are not growing quite as fast. I am no longer working outside of the home due to my need to care for 2 ankle-biters, but once upon a time I did work at a botanical garden as a horticulturist. What did I do? I watered, pruned, weeded, answered a thousand visitor questions per day, and paid attention to all the details that make a garden look truly spectacular. Autumn was not a lazy time, but an energizing time to be in the garden. I am going to briefly discuss one aspect of fall garden maintenance that can really result in a cleaner appearance; perennial maintenance.
What is a perennial? A perennial is any plant that lives for more than one year, typically we are referring to those that live for 3 or more years. So a perennial can be a tree, shrub, or even a weed. What I will specifically be discussing here are herbaceous perennials. Herbaceous perennials are those that are non-woody and typically go dormant or die-down for the winter and reappear in the spring. So when you see that your bleeding heart is turning brown, no need to worry, it will be back in the spring.

How do you care for your perennials when they are turning brown? Short answer: cut them to the ground or leave them alone. Technically you don't have to do a thing to them, but reasons of aesthetics and pest/disease management I recommend cleaning them up.To cut them back you simply use a pair of pruners or scissors to cut them all the way to the ground or you may gently pull the leaves away if they come without resistance. Here are a few points to consider when deciding to cut back your perennials:
1)Brown is Better: The more you let the leaves and stems turn the brown, the more nutrients the plant has allocated to the roots. In the winter time, roots continue to grow while the top rests, but the roots need all the nutrients they can get from the top of the plant. When it is completely brown, the food transferring job is already done; go ahead and cut it.
2) Bit by Bit: If you don't like the sight of the dying plant, you can do as I do and cut out sections of the browning plant little by little until the whole thing is gone. Don't be afraid to cut in random patterns, you will not be doing damage to the plant at this point. At some botanical displays it is required to cut the plant back before the plant has died down, but this adds stress to the plant and the following season may not be quite as spectacular in growth and blooms. Doing it in sections is a nice balance for maintaining a good appearance and health.
3) Pest Management: Sanitation is one of the key elements of IPM (Integrated Pest Management). IPM is an all encompassing method of controlling or treating diseases or pests by starting with the most natural methods of prevention and defence and only resorting to chemical treatments when other methods have been exhausted. Sanitation involves clearing dead leaves and debris that accumulate beneath a plant. or cutting out sick or diseased portions of a plant. many pests or spores perpetuate by incubating eggs or pupae in the dead debris that eventually transfer to living plant materials. By removing unnecessary perennial foliage in the fall, you are helping to keep your garden clean, tidy, and disease/pest-free.
4) Exceptions: Some plants you may want to leave when they turn brown because there is some artistic value in the winter months. For example, grasses are typically enjoyed until January because of the soft look they have in the bare winter landscape. Autumn Joy sedums are also valued for the way the look all dusted with snow int he middle of winter.
5)Have Fun!: This is probably one of my favorite garden tasks. What gardener doesn't like the satisfaction of pulling out the pruners and cutting away? Well, this is a great opportunity to hack away without obsessing too much about doing something wrong. You will also love how nice your garden looks when you are done!

Examples of common herbaceous perennials in the garden: peonies, bleeding heart, hosta, many bulbs, daylilies, lilies, black-eyed-susan, most daisies and mums, grasses, veronica, coral bells, and many more.