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September 2020 Master Gardener Column

Perennials and annuals have had a great run this summer, putting on a bounteous display of color. I’ve never seen some of my plants so covered in flowers. Right now, my buddleias (butterfly bushes) are so full of blooms the green leaves and stems are barely noticeable, much to the delight of the butterflies, bees, and me.  If you are new to flower gardening, you chose a great year to get started.

Still to bloom in September are the mums, asters, sweet autumn clematis, autumn joy sedums, and goldenrods.

Unfortunately, this was not a stellar year for vegetables. In talking to other gardeners, I discovered most had the same problems which lead me to think it was probably weather-related and not due to plant variety or soil problems.

The following is what I’ve been hearing. Yields were disappointing compared to previous years. Tomato plants were small and compact, never achieving their full height. The fruit looked good, but there was less of it and the taste was underwhelming. On the other hand, green beans grew large-leafed, lovely bushes, but the yield was small and very slow producing. So, if you are a new vegetable gardener, take heart, it wasn’t you. Next year will be better.

September starts the fall transplanting season. If you have perennials that need to be divided and replanted or shared with others, now is the time to get started. Plant them at the same level they were growing in their previous site. As always, keep them well hydrated up until the first frost in October. Do not fertilize perennials in the fall, especially newly planted ones.

Keep an eye on your pumpkins. If the ground stays wet from a lot of rain, you may need to pop some straw under them to prevent a yellow area on the skin. Squash bugs might start chewing on the skins, marring that perfect orange desired for jack-o-lanterns.

Even if the Dutch bulb companies send your order of bulbs, September is too early to put them in the ground. Wait until October and November, preferably after a good hard frost. September is also too early to dig up your tender bulbs and corms, etc. After a frost is best when the top growth is going dormant.

You can start the dormancy period for amaryllis. Stop watering and let the soil dry out completely. If any leaves remain, wait until they turn brown and remove them before moving the amaryllis, pot and all, into a cool dark place that doesn’t freeze.

The Illinois Extension Master Gardeners of Edgar County encourage you to enjoy this last month of the active gardening year. For questions, please leave a message at 217-465-8585 or email us at