SEPTEMBER
While many gardeners are setting their sights on fall planting and cooler weather, step outside and you are still smack-dab in full-blown summer. This late August weather is hot, humid and for the most part, dry.
◼️ Fall color is arriving at nurseries and garden centers statewide. While it is time to start transitioning from summer to cool season plants, be careful what you plant and when. Cool-season annual flowers and mums can succumb to excessive heat if they don't get enough water.
◼️ If your garden needs some quick color, you can replant some warm-season plants, such as ornamental peppers and marigolds, or petunias and calibrachoa, which will survive until a frost and give you great fall color. These plants can take the heat, too, provided they get enough water.
◼️ Dianthus, ornamental kale and cabbage — along with the edible ornamental Swiss chard, purple mustard and kale — can all be planted now.
◼️ Violas will tolerate more swings in temperatures than pansies will, so consider adding a few as temperatures go down. Hold off on pansies until the hot weather is gone. Pansies get leggy quickly if exposed to too much heat.
◼️ Make sure you don't forget to water. Keep your fingers crossed that September is not miserable, because it can be. Pay attention to rainfall (or not) in your yard, since water right now is critical.
◼️ Spring-flowering shrubs and trees — along with fruit trees and blueberry bushes — are setting flower and fruit buds for next year. If they get too stressed, it can affect your flowers and/or crops next season, so water when dry. It is too late in the season to be worrying about pruning or fertilizing these crops, but do continue to fertilize summer annuals, vegetables and tropical flowers. Make sure plants are well watered before applying fertilizer when it is hot and dry, and apply it sparingly.
◼️ While some plants have slowed down in their growth with the excessive heat, summer weeds are having a fine time. Chambers bitters, mulberry weed and pigweed are all summer annuals that are growing by leaps and bounds, blooming and setting copious numbers of seeds to haunt you next year. Try to pull or hoe out as many as possible to reduce problems next year.
◼️ Perennial weed-vines like Virginia creeper and poison ivy will be preparing for dormancy in another few months. If they are growing well and healthy, now is a great time to spot spray with Roundup to kill them. Make sure you direct the weed killer only on what you want to kill.
◼️ We have not had the easiest growing season, and this late season heat and humidity coupled with the driest conditions we have had mean many plants are shutting down early. Leaf spots, yellowing leaves and mildew have been a common complaint. I doubt you will find many hydrangeas without a spot here and there, or healthy-looking red buckeyes, or peonies with a full set of green leaves. Don't worry and don't start spraying.
◼️ This late in the season it is time to clean-up, water when dry, and prepare for dormancy. Any perennials that have started dying back or have dead or diseased leaves can be cut back now. That includes peonies, lilies and bleeding hearts. Once the leaves begin to decline, their season is over, and they will be fine until they reappear next spring.
◼️ Trees and shrubs with damaged foliage should be monitored for leaf fall. Once that begins, rake it up and clean it up so they can start fresh next spring. Don't prune trees and shrubs now — especially spring bloomers — as they have set their flower buds for next spring.
◼️ Eggplants and peppers are still producing pretty well in most gardens, so continue to harvest and enjoy as long as they last.
◼️ Some gardeners had better success than others in the summer vegetable garden, but many plants are getting tired. If you can find transplants, you can put in some fall tomatoes and peppers. You can also begin to plant cabbage, broccoli, greens, lettuce and radishes. Mulch any new plantings and water. With just a little bit of protection, we can now produce edibles year-round in a home garden.
FASTIGIATE SWEETGUM TREE
The native sweetgum tree Liquidambar styraciflua is one of the prettiest fall foliage trees in Arkansas, but if is often accompanied by the dreaded sweetgum balls — the fruiting body of the sweetgum tree.
While sweetgum balls actually make a nice mulch to deter slugs around hosta plants, they aren't fun to walk on, so only rarely have gardeners intentionally planted a sweetgum tree in their yard. Rarely, that is — until the fastigiate, or columnar, sweetgum trees were introduced.
Slender Silhouette was the first, but there are other varieties out there as well.
These trees look like something out of Dr. Seuss with narrow, wispy crowns. They grow no wider than five feet or so, but they will get as tall as 75 feet over time. They give us the vertical height we sometimes want in limited space.
They are tough performers, take full sun and are fairly drought tolerant as well.
A fastigiate sweetgum will produce sweetgum spiny fruits eventually, but usually not until they are 5 to 7 years old, and gumballs aren't as prolific on this variety as they are on a standard tree, but then, there aren't as many branches either.
Read Janet Carson's blog at arkansasonline.com/planitjanet.