Perennials, Annuals and Vegetables
Plant spring-flowering bulbs!
Lift and divide existing spring flowering bulbs, if necessary. Also a good time to lift and divide overgrown or crowded perennials, replanting into soil amended with compost.
It's still not too late to plant some vegetables for the fall and winter vegetable garden. Overwintering types of Broccoli, Cabbage, Collards, Cauliflower and Kale can be planted by starts. By seed, salad greens and Merida type carrots are still possible. If you have row covers, cloches or other protection for crops, the possibilities are wider, still.
It's one of the best times of the year to plant perennials! (See General Tips section.)
Tidy up annuals and trim back spent growth. Feed with a water-soluble fertilizer to encourage some annuals to put out one last round of bloom before frost.
Plant the newest crop of pansies ("Winter Pansies") to add some fresh color to the garden.
Consider planting an overwintering COVER CROP on unused vegetable beds or bare areas in flowerbeds that won't be planted until spring. The fall and winter rains will beat bare (even amended) soil back into hard clay, effectively undoing all your hard work in preparing the area. Planting an annual clover, cereal grass or legume cover will soften the rain's blows, and in some cases even fix additional nitrogen into the soil for greater fertility. Tilling in this "green manure" in the spring before it puts on too much growth will add still more organic matter, improving the tilth and texture of the soil still further. It truly is one of the best things you can do for your soil. At Portland Nursery, we carry several types of cover crops, suitable for every soil condition and situation in your garden.
Questions about harvesting vegetables come up this time of year, especially as the weather starts to cool and we realize with a bit of a shock that we're witnessing the declining days of summer...
- Melons — Most melons will detach from the vine with pressure from just one finger when ripe. And melons do not continue to ripen off the vine, so be careful not to harvest too early!
- Squash — Summer Squash are best harvested while still on the small side, because not only is the flavor better, but if left on the plant a long time it begins seed formation and reduces further fruit set. A Winter Squash is completely mature when the stem is brown and shriveled. But usually our summers don't last long enough for that to occur; to optimize harvest, you can remove the very smallest squash and any new ones from the vine after September 1st, in order to allow the plant to put the remainder of its energy into ripening the larger fruit. Harvest before powdery mildew or a first frost has destroyed the leaves, and wipe the skin with a disinfecting bleach solution. Cure the skins by letting the squash air dry at room temperature for a week or so, then store them at about 55° and low humidity for longest keeping.
- Eggplant — Best if picked when slightly immature — when the fruit has stopped rapidly enlarging, but the skin is still shiny and thin. Fruit set stops a week or two before the autumnal equinox, and this is when all developed fruit should be harvested. Smaller fruit may continue on to ripeness if the early days of October are sufficiently warm.
- Peppers — Many varieties of both sweet and hot peppers change color from green to red or yellow as they ripen, and as much as possible this should be used as the guide for harvest for best flavor. For thin-walled varieties of hot chili peppers that are intended for drying, be sure to harvest before frost or the onset of the rainy season to prevent rotting of the fruit. If the fruit has not entirely ripened by this time pull up the entire plant and hang upside down in a cool, dimly lit place. Some of the remaining fruit on the plant will both ripen and dry under these conditions.
- Tomatoes — Tomatoes are at their peak when they easily detach from the stem with only the slightest tug. But what to do as summer wanes, and you are still facing green globes on the vine? You can boost the ripening of the larger fruit by removing all flowers and the smaller, immature tomatoes, beginning about September 1st (these smallest of fruits won't have time to mature, in any case). An additional method is to start withholding water in late August/early September. This stress will cause the plant to ripen its fruit, thinking that it must hurry to ripen its seeds for reproduction. Watch out for late summer rains, however, which can cause these now more fragile vines to fall apart and become diseased. In the almost inevitable event of some green tomatoes: if they are full size at harvest, many will often ripen in the house (but search out some recipes for green tomatoes, just in case!).
It is well into the time to be planning/planting your fall and winter crops, too, both from seed and transplants! The cooling temperatures may be signaling the waning of the summer crops, but it also ushers in the beginning of the next round of a wide variety of greens and other cooler weather crops.
Lawn Care
While the soil is still warm, it is a great time to seed a new lawn, on the heels of the fall rains that will aid germination. Shorter days mean slower top growth, allowing plants to store more nutrients and be in optimum condition for good, healthy growth next spring.
Trees, Shrubs and Fruit
Lightly feed roses after their fall bloom with a granular, organic/slow release fertilizer like the Whitney Farms Rose & Flower Food. By being a slow release fertilizer, it ensures that the plants have the right nutrients as they go into dormancy. At the same time, it doesn't feed so rapidly as to cause a spurt of tender new growth that would be vulnerable in the cold winter months. Also, LEAVE THE HIPS ON THE ROSES! They help signal the plant to go into dormancy.
General Tips
It's true — Fall is for Planting! The soil is still warm, providing faster root growth and giving plants a head start on next year's growth. By next summer, they will have a larger, more established root system than spring plantings — means better drought tolerance and better flowering the first year. Also, the shorter days and mild temperatures in fall mean lower stress on new plants Last, but not least, the inevitable rains help keep those new plants watered-in, meaning less work for you (maybe a few days left to enjoy the hammock).
Exception: Plants that are frost tender, or borderline hardy for your area are best planted in the spring, unless they are being put in a well-protected area.
Pervoskia - Russian Sage
SEPTEMBER TIPS - VIDEOS
CLICK PHOTO TO PLAY VIDEO. Videos will load automatically. Visit the GardenTime TV website for more GardenTime videos.
Jan McNeilan's September Tips
Oregon Invasive Plants
Creating Hypertufa Containers
Amdro Ant Block
Summer Tree Problems
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