Monthly Archives: September 2012
I hope you’ve been enjoying the videos and posts on fall gardening while I’ve been out. They will continue for a few more weeks, as I’m still going to be out of the office for awhile. I’m busy at the moment, mostly with this…
She had her first outing to our community garden plot at 10 days old!
Meanwhile, things have still been going on back at the Demo Garden…
Those ugly, damaged tomato plants finally set tomatoes…They were pretty much covered with green tomatoes last weekend! Unfortunately for them, the tomato bed is going to be converted to garlic next week.
The lettuce we transplanted in the Family of 4 garden and a couple of the other beds a few weeks ago is looking great! I really missed having cool season veggies like lettuce in the garden this past spring.
Well…most of the lettuce is looking good. Apparently these friendly caterpillars found their way to our lettuce patch. UGH.
The Mexican Oregano was in full bloom over the weekend. It was a very attractive plant this year and definitely thrived in the heat. Unfortunately, it got a little bit swarmed under by the melons on the trellis next to it. I also didn’t have time to do any cooking with it to share with you.
It still boggles my mind that the jicama could sit there and pretty much not grow at all for most of the summer, and then all of a sudden take off, almost like the magic beanstalk. I’m not sure if the jicama survived this week’s clean up in the garden and if it had time to develop any tubers. I’ll let you know if I hear anything.
A commenter asked a couple weeks ago how the lemongrass that I started from stalks from the grocery store turned out. I took several pictures and decided that this one was the best to show the size and scale of the plants. Otherwise they just look like a mass of green. The lemongrass plants are right next to one of those cattle panel trellises….just like we have in the Demo Garden. I would say that the lemongrass is at least 4 feet tall. It is also providing some nice shade to the lettuces that are planted under the trellis. I haven’t used any of the lemongrass yet, although I did cut a couple of stalks, just in case I had the time or inclination.
While heat is the biggest challenge when planting your fall garden, by the end of fall there is the challenge of cold weather. In an average year, the first light frost will usually occur in mid- to late October, although sometimes the first frost occurs sometime in November. A light frost, where the low temperature dips down to 30-32 degrees will not damage fall vegetables. The cold may even improve the color and flavor of the vegetables. Most fall vegetables will tolerate temperatures down to 28 degrees without significant damage. In fact, allowing exposure to below-freezing temperatures will often allow the plants to better adapt to the cold, increasing their hardiness to later cold weather.
On a cold morning before the temperature is back above freezing, your plants may look wilted and permanently damaged. However, by the time the temperature is back above 32 degrees, they will recover and continue growing. It is important not to harvest these fall vegetables until the temperatures are back above 32 degrees and the plants have naturally recovered from the frost.
When low temperatures dip below the mid-to upper 20s, it will be necessary to protect semi-hardy fall vegetables with a light row cover to minimize damage on those vegetables. Some particularly hardy vegetables, such as spinach and kale, will not need extra protection until the low temperature is near 20 degrees.
It is usually best to remove the row covers during the day to allow the sun to warm the soil more efficiently when we are still getting intermittent frosts. As we get later into the year, leaving the row covers on may help create a mini “greenhouse effect” and prolong your growing season once we are regularly dipping into the 20s overnight.
We talk a lot about soil testing, but it is also important to know what is the texture of your soil.
Okay, I know this is a little bit after the fact, but now you know, right?
Dealing with Late Summer Heat
When establishing vegetables during late summer heat, there are several techniques that can make your plantings more successful. Using shade cloth, mulches, transplanting, and careful watering will all improve your fall garden success.
A white or black, lightweight shade cloth can be used either close to the soil surface to help with seed germination or 1-2 feet above the ground to provide light shade to seedlings and transplants. The shade cloth will help cool the soil and the air temperature around the plants, as well as reduce moisture loss from the soil. A shade cloth that is too thick or heavy will reduce the light penetration too much and can reduce air flow, resulting in poor germination or plant growth. The shade cloth should be removed either after seedlings or transplants are well established or when the temperatures become more moderate.
Mulches of organic materials (straw, shredded paper, wood chips, herbicide-free grass clippings) have the effect of cooling the soil. They will also help keep the soil more evenly moist when germinating seeds. These mulches can be applied very close to the seeding row or around new transplants. It can be very effective to apply the mulch to an area up to 2 weeks before planting, allowing the soil underneath to cool slightly. Then the mulch can be pulled back for seeding or transplanting later.
Later in the fall, mulches can be removed to allow better warming of the soil by the sun to encourage late fall growth.
Some fall garden vegetables must be planted by transplants to provide a long enough growing season. Broccoli, cauliflower, cabbage, onions, leeks, and radicchio will all do best if seeds are started indoors 4-6 weeks before transplanting. Onions, leeks, and radicchio are often very slow to grow from seed and may need to be started even earlier. Root vegetables (beets, carrots, radishes, and turnips) do not generally transplant well.
Starting leafy greens and similar vegetables indoors allows them to get a good start when the weather may still be too hot outdoors. For example, lettuce started in late July will be ready to transplant into the garden by late August, giving you a 4 week head start on your fall lettuce crop. You can then seed additional plantings directly in the garden if desired.
When transplanting vegetables in the late summer, it is important to give the plants a chance to adapt to the warm and windy outdoor conditions. Plants should be set outside for 1-2 weeks to adapt to the brighter light and higher temperatures. The first day, place the plants in a protected location with partial shade for only a few hours. Each day for 7-10 days, they should be placed in a location with more exposure to the sun and other elements. During this time they should receive adequate water, but not excessive water so they can adapt to drier conditions.
Managing Water Needs
When direct seeding in the garden in late summer, it is important to keep the top 1-2 inches of the soil evenly moist to facilitate seed germination. Typically the seeds will germinate quickly due to the warm soils, and then you will need to gradually reduce watering to encourage deep root growth.
Likewise, newly planted transplants may need more water initially, but you should decrease watering quickly to encourage deep root growth.
As the weather cools and we experience more frequent fall rains, less water will need to be applied. In some falls, there will be adequate rainfall for a successful garden. Most fall gardens will need about 1 inch of water each week after the heat of the summer has passed.