What’s going on in the Greenhouse…

As summer fades away and autumn is upon us, the shorter days and cooler nights bring out the best in fall blooming plants. A favorite of many gardeners is the chrysanthemum, but most of us just call them mums. This easy to grow plant gives us some serious flower power at a time of year when there is not a lot of flower color from trees, shrubs and many perennials.

You'll find lots of mums in front of the grocery store. Buyer beware! Many mums are what I classify as 'decorator' plants - these are not hardy mums but are great used in late summer mixed containers. They won't, though, survive our harsh Minnesota winters in our gardens.

If you are looking for long lived perennials that will come back every year in your garden, you need to keep an eye open for any of the mums that were developed right here in Minnesota at the University of Minnesota. They've been breeding hardy mums at the U of MN for years, and there are many great varieties to choose from.

The newest breeding work from the U of MN is really exciting - it is called the Mammoth™ series of mums, and it is appropriately named! These are mums that are truly crown hardy, and once established in the garden, a mature plant can easily reach 3' in height and 4' in spread - now THAT is big! So, don't be fooled by the small, one gallon or two gallon pots you might see at the grocery store - read the tag and double check just how big your mum will get when you place it in the garden.

These mums have very simple cultural needs: they need a full sun site, meaning they need at least 6 hours per day of direct light in the garden. They need well-drained soils, meaning they won't tolerate really dry, sandy soils nor really wet clay soils. You'll want to pinch any early spring flower buds off of the plants until the fourth of July, and then allow the buds to develop. In the late autumn, they need no special winter covering, you'll just want to cut down the frosted stems and they will emerge from the crowns the next spring.

There are a number of colors available in the Mammoth mum series, and the majority of these varieties have more of a daisy type of flower, rather than the multipetaled types we normally think of with mums. They will typically start blooming in mid to late August and will provide a huge mound of color all the way through September and even into October.