Radio Silence

Our radio show, "Garden Talk," was abruptly cancelled last week when the station underwent a change in format from news/talk to alternative rock. Such is life these days in the radio business, or at least that is my understanding.

My co-hosts, Dr. Sue Hamilton and Andy Pulte, who have been doing the show much longer than I have, are determined to bring it back to the airwaves before next spring. We are researching possible venues and mustering our arguments.

I will update listeners as new information becomes available. In the meantime, folks can continue to send questions to knoxgardentalk@gmail.com or to post questions and photos on our Facebook page.

Readers of this blog are invited to send questions via the email link on the home page.

We welcome comments, suggestions for improvements, and anything else you would like to share regarding the "Garden Talk" program. Our plan is to create an even better, more informative, and more entertaining show as we seek a new, larger audience.

Although the 2015 garden has yielded up just about all of its delights, the current warm spell is prolonging the harvest for some crops. We are on track to have a great harvest of fall peas, especially given the good soaking rains we have received the past few days. We continue to harvest parsley and scallions, kale will be ready any day now, turnip greens are coming along, and the cilantro is lush and delicious. All indications point to some harvest well into November.

We have started some indoor crops that are thriving under artificial lights. If you like the flavor of fresh basil, but are appalled at its cost in the grocery store, your best bet is to grow a pot of 'Bush Spicy Globe' in a south-facing window or under lights. This variety has excellent flavor and will reach the size of a volleyball in a six-inch flowerpot. Grow it in any commercial potting mix, adding a half-teaspoon of timed-release fertilizer at planting time. You could also mix in an organic plant food, following the instructions on the package. Basil needs little attention, other than regular watering. Don't let the soil get dry enough for the plants to wilt. Clip sprigs for the kitchen judiciously until the plant is at least as large as a softball. Thereafter, you can snip with greater abandon. Keep plants producing by removing flower buds as they appear.

Want to start a vegetable garden next year, but not sure where to begin? Email for information about our Home Food First program. It's designed to help first time gardeners succeed, like having your own personal gardening coach.

Plant Fall Greens Now!

The coming week will be your last opportunity to plant fall greens. Some of the best performers for this time of year are kale, mustards, and turnips.

Kale and other brassica plants are showing up in the garden centers. It is too late to start broccoli and cabbage from seed, but kales, especially the really cold hardy ones like 'Red Russian' and 'Lacinato,' will be able to make decent growth before the first frost. The plants are sufficiently cold hardy to provide a harvest well into December.

With about 45 days remaining until the first expected frost, look for greens crops that will mature quickly. Top choices include the turnip variety 'Seven Top,' and various mustards. Mizuna, tatsoi and bak choy. These Asian mustards will all mature before it gets too cold, as will both curly and red European mustard varieties. Also in the mustard family, radishes will have plenty of time to mature before frost. You can get in 2 or 3 sowings, a few days apart, between now and the end of the month. Another good choice is arugula. Plant small amounts every few days for a succession of crops in October.

All these greens are good in salads when they are small, and can be used as cooked greens when they get larger.

Garden centers also have lettuce plants in cell trays. If you don't already have some lettuce seeds germinating, the commercial plants will give you a quick crop or two before frost reduces the quality.

While you are at the garden center, why not purchase a row cover tunnel for your garden? Using one of these tunnels will protect late crops from frost, and extend the growing season by a week or two at least. Given the cost of fresh salad greens, the small investment in a row cover is paid back the first season in our garden.

Rain, Finally

Finally! Some serious rain. According to the National Weather Service, our area has had a deficit of about six inches for the year. It appears we may be on track to make up much of that deficit during the current rain event. This could not have come at a better time for many crops, such as cucumbers, melons, and squash. These vegetables are about 90 percent water, so having enough soil moisture as the fruits are maturing is important.

The downside of the rain is the greater tendency for many of our warm weather crops to develop problems with fungal disease. Cloudy, wet weather favors mildew, blights, and other problems. If plants have been spaced properly to allow for good air circulation, you have the best defense against these problems. We can also hope that the rain will let up for a while and a period of sunshine will ensue. This is the ideal situation, allowing foliage to dry off and the pace of photosynthesis to increase.

From now until about the end of August, vegetable gardens around the region should be at their peak of variety, abundance and flavor. If you plan on doing some home canning with produce from the farmer's market, this is a great time to stock up. We have regional markets every day of the week, and the big market in Knoxville takes place on Wednesdays and Saturdays at Market Square.

Backyard gardeners will be harvesting everything from late beets to early corn. Just about the only crop that won't be ready yet is okra, which usually waits until August to make its debut. We have had great success with heat tolerant lettuce varieties this year, and as a result we still have a couple of heads in the refrigerator for dressing sandwiches. Having lettuce past the Fourth of July has been a real treat. In case you missed the earlier post, the variety we like best is 'Jericho.' It is sort of a cross between romaine and butterhead, and remains sweet and tender despite the punishing heat we had in early July. We will definitely plant more of this one next year.

As long as the rain hold up, about the only chore you have in the garden at this time of year is weeding, which the rain actually facilitates.

And don't forget, it's time to start thinking about fall planting. If you intend on growing cabbage, broccoli or another member of that group, July 20 is the date for starting seeds. This gives you plants ready for the garden by August 20, and allows 90 days of growth before the first freeze, expected around November 20. The average first frost date for this area is October 20, so frost-tender crops will need to mature in under 90 days if they are planted now. Cucumbers and summer squash are a possibility. Virtually all the cool season crops can be planted between now and August 20. Top choices are beets, carrots, leeks, peas, and turnips. Fast maturing leafy greens, such as spinach and mustards, should wait until mid-August or the seedlings may die from summer heat.

Root Crops and Dwarf Berries

Get those root crops in the ground! March is a great time to plant beets, carrots, onions, turnips, potatoes and radishes. If you planted radishes last week, chances are they are ready to thin. As we discussed on "Garden Talk" this morning, thinning is essential for many types of food crops. Although it is often difficult to convince beginning gardeners to do so, thinning actually increases yield, because each plant has enough room to perform at its best.

In the case of radishes, they should be thinned early, before true leaves have appeared, for the best quality roots. Leave about two inches between plants. Carrots also demand thinning, and the delicate seedlings should not be left crowded too long. Carrots planted this week will probably not appear above the surface until early April. Besides the approaching cold snap, natural germination inhibitors keep the seeds dormant until they have been wet a few times. Thin carrots to stand three or four inches apart for the largest, most uniform roots, unless you are growing a smaller variety, such as 'Little Finger.' Do this as soon as the feathery true leaves begin to appear. In the case of both radishes and carrots, it is best to snip off the excess seedlings at soil level, rather than pull them, because pulling may injure the roots of neighboring plants.

Radishes and carrots may be planted together in the same row. By the time the carrots germinate, the radishes will be almost mature. The emerging radish seedlings break the soil surface, making it easier for the weaker carrots seedlings to follow them. When you harvest the radishes, you will automatically thin some of the carrots.

For gardeners who just hate to thin, I suggest using seed tapes. They are available for many popular varieties of vegetables with small seeds or that are difficult to thin. Essentially, seeds are evenly spaced out between two thin strips of paper tape. You simply lay the tape in the row and the seeds end up at the correct spacing. This is a big time saver, but the tapes are expensive compared to loose seed.

March and early April provide perfect weather for transplanting nursery stock, and all varieties of fruit and flowering trees and shrubs are showing up in local garden centers. This year, check out the Brazel-berry varieties of blueberries and raspberries that have only recently been introduced into the market. "Brazel-berries" are dwarf varieties of raspberry and blueberry, suitable for small garden spaces or even patio containers. 'Raspberry Shortcake' offers the added benefit of being thornless. Grow it in neutral soil in full sun and harvest berries in mid-summer. The two new brazel-blueberry varieties being offered at Stanley's Greenhouse this year are 'Peach Sorbet' and 'Jelly Bean.' Like standard blueberries, these shrubs prefer acid soil, and can be included in the landscape alongside sun-loving azaleas, such as Encore(TM) types. All the brazel-berry fruits can be grown in large containers, making control of the soil pH simpler than in-ground growing. Besides the obvious benefit of fruit, all these shrubs add color and interest to the landscape. Blueberry foliage turns pink and purple in the fall, too. More information and images at www.brazelberries.com

Spring Planting Tips

Tonight the Full Worm Moon will illuminate the landscape, provided the clouds clear out to enable us to see it. Spring arrives officially this Thursday, and, coincidentally, Thursday, March 20 is one month prior to the average frost date (for my location), April 20. Rain began overnight and continues to fall, irrigating our raised beds, now bursting with green onion, leek, shallot and garlic tops from last fall’s planting.

Lettuces that were started in cells trays last week are now up and will soon have true leaves. I am growing them under the LED light I have mentioned previously. I note that the red-leaved varieties color up soon after germination, an indication they are getting plenty of photo-energy.

St. Patrick’s Day, Monday, March 17, marks the traditional time to plant Irish potatoes in East Tennessee. I also find this memory aid helpful in reminding me when to place a sweet potato root into a jar with water, so that I will have slips ready to plant around Memorial Day. Sweet potatoes require heat, so sprout them in the warmest, sunniest spot you can manage indoors. Otherwise, you will be better off to purchase slips, which will appear at better garden centers at the appropriate planting time. Two good bets for the Knoxville area are Mayo Garden Centers (several locations) and Knoxville Seed and Greenhouse Supply (Rutledge Pike).

This week is a good time to plant root crops, according to the traditional practices based on the moon. When the moon is waning, plant vegetables that bear below the ground: beets, carrots, onions, potatoes, radishes, and turnips. Note that Asian radishes are likely to perform better here if fall-planted, but salad radishes seem to do best in spring.

You still have time to transplant cabbage and broccoli, but the window is pretty much closed by the equinox. Spinach, also, will soon not have time enough to mature before the weather gets hot.

If you have not planted asparagus, you should get roots in the ground by the equinox, also. Otherwise, you may find the stock at the garden center has already begun to sprout. Not a good thing, because if you break one of those tender shoots, you rob your plants of vitality needed to establish a healthy root system. Good roots are crucial to productivity during the second season of growth. If you already have an established asparagus bed, now is the time to apply a balanced organic fertilizer, topped with an inch or so of good compost or composted manure, such as Black Kow™. Top that with an inch of mulch, such as straw, pine needles, or shredded bark. Doing so now gives the nutrients time to be decomposed by soil bacteria, making them available to the asparagus plants when they begin sprouting a few weeks hence.

Don’t forget to tune in to 94.3, WNFZ, Knoxville, for “Garden Talk,” every Saturday morning at 8:00 AM. I’ll be there to talk about vegetable gardening and other topics with Dr. Sue and Andy the Garden Guy. Our sponsors are Stanley's Greenhouse and Ellenburg's Nursery. Visit your local, independent garden center for plants, supplies and good advice!