Time to trim fall garden

Cool evenings, warm afternoons and a few colored leaves tell us we are entering the last few weeks of summer. We will certainly have wonderful late summer weather ahead but we need to be mindful that fall is around the corner. Make time for those end-of-summer tasks and also make time for those end-of-summer joys.

One of the happy tasks of fall is my trip to the garden center in search of new or replacement perennials for my garden. Getting new perennials established now will give us a good showing next season. Don’t neglect the fall perennials. There is hardly a garden that could not be improved with a few more fall perennials. While planting my new plants, a few established perennials that are being crowded or have outgrown their location need attention too.

There are a few rules to keep in mind as we plant and or divide and transplant perennials. Always plant on a cloudy day or plant in the evening. Many of our perennials have recently bloomed, and being uprooted and moved may compromise their health. With that in mind, shade new transplants for a day or two if they are in a sunny location. The best time to plant is when the temperatures are cooler. A stretch of cool, cloudy autumn weather is a great time to plant or transplant.

Take the time to choose your site carefully. Dig your hole so the plant sits at the same depth as it was before the move and at least two to three times the width of the plant. This is the only time you can amend the soil so make sure you have a good supply of compost on hand to mix into the soil in the bottom of the planting hole

Cut foliage back by one-third to one-half to minimize moisture loss through transpiration. Mulch the new plants or transplants and most important, water well and water often. This is also a good time to put some spring bulbs near the new perennial. As the perennial blooms next summer the foliage will cover the unsightly foliage of the spring flowers.

Except for fall blooming perennials, do not fertilize after the middle of August. You want the perennials to prepare for dormancy. I do apply liberal amounts of compost and cow manure. This is more of a soil amendment than fertilizer but it does seem to give the perennials a little boost in the spring.

Likewise do not prune your shrubs. Go ahead and prune anything that is broken, or branches that cross but other than that pruning stimulates growth and the bushes need to be slowing down not putting out new growth.

The established perennial border can start to look shabby now. Keeping the flowers deadheaded allows your perennials to put their strength into growing healthy roots and preparing for the next season. Cut back any foliage that is brown or unsightly. If you see any mildew or fungal disease remove that now and put in the trash not the compost. When cutting perennials back in the fall be sure to leave a few inches of plant to protect the crown over the winter.

In late summer our containers begin to show an overgrown leggy appearance. Cut back the annuals to encourage flowering. I try to stagger my pruning so the container still has flowers by cutting the shaggiest first and over a period of a couple of weeks rejuvenating the container. Some annuals just cannot be brought back and need to be composted. Don’t overlook combining two containers with some new fall annuals. An all foliage arrangement with a silk fall leaf or two make a beautiful container. The trick here is to use the silk leaves sparingly.

Keep weeding. Every weed you allow to go to seed will only compound the weed problem next season. Weeds steal nutrients and water from your plants. They grow close to your plants and often ruin the shape of the perennials. I also keep my garden bed edges crisp and mulched. Think of it as good grooming in the garden. I love my autumn garden and I am proud of it.

If you have house plants outside, get them ready to come back inside. Chilly evenings may damage your plants. Spray house plants with an insecticidal soap, available at the garden center. After a week spray the plants again to kill the insect eggs that have hatched since your first spraying. I pour soapy water down through the soil of the plant to kill insects that are hiding there.

This is a good time to divide houseplants that have outgrown the container. It is a lot easier to do this outside at a newspaper covered picnic table than at your kitchen counter tops. I also clean up the containers before I bring them indoors. To bring houseplants in now while the windows and doors are still open will allow the plants to still enjoy some humidity.

I get questions this time of year about hardy mums that are sold in our garden centers. These plants are called hardy because they can withstand the light frosts and cold temperatures of the autumn night. If you plant this hardy mum in your garden it does not have enough time to get established and might or might not come back in the spring. Planted in the spring, when these plants are usually not available, would give them time to get established. They will never be neat, round balls of color again. That takes the professional. To try to replicate that look mums must be pinched back in early summer.

I buy three large mums every fall to place at the end of my drive and beside our rural mailbox. I cannot duplicate the shape or size of these special plants but they “make” my autumn garden. Besides, you are supporting the local farmer who grows these wonderful plants.

“Summer’s lease hath all too short a date (William Shakespeare.” Keep up with the garden chores but make sure you enjoy this beautiful month. When you make a list of jobs be sure to schedule naps in the hammock, a walk in the woods and the last supper on the porch.