Vegetable Gardening Page 11
Onions in particular like lots of fertilizer, and they can stand some extra nitrogen, which promotes leaf growth. Add extra fertilizer when the transplants are 6 inches tall and the bulbs begin to swell. Then add a complete organic fertilizer, such as 5-5-5, at 1 pound per 10 feet. (See Chapter 15 for more on fertilizers.)
Root crops, especially carrots and onions, require proper spacing to grow at their best. Thin out the young seedlings when they're 3 to 4 weeks old by pulling them out or snipping them until they're properly spaced (see Chapter 13 for details on thinning seedlings). Onions should be 4 inches apart, scallions 2 inches apart, and carrots 3 inches apart. Potatoes don't need thinning and should be planted 8 to 10 inches apart when planted.
I know that thinning your hearty crops sounds cruel, but if you don't do it, the roots won't have enough room to expand, causing you to get lots of plants but few roots — and fewer roots means fewer carrots and onions.
You'll be rewarded with lots of crisp roots in no time if you regularly weed your root crop patch. After a good thinning, hand-weed beds of carrots and onions; potatoes can be weeded with a hoe. Mulch the bed with hay or straw. You don't have to mulch in between individual onion and carrot plants. Simply mulch around the beds, and keep them well watered.
Carrots, onions, and potatoes are root crops that like cool temperatures. They grow best and have the best flavor when temperatures stay below 80 degrees Fahrenheit.
Cultivating carrots
Carrot seeds are small and take up to 2 weeks to germinate, so you run a greater risk of poor germination with them than with other vegetables. To get your carrots off on the right foot, try these tips:
Prevent forked roots in carrots by making sure the soil is free of rocks, sticks, and hard pieces of soil. If carrot roots come in contact with a hard object as they're growing, they fork, creating a multipronged carrot. Even though they're interesting to look at and a conversation piece at dinner, forked roots are harder to clean and yield fewer carrots. No soil can be completely free of rocks and sticks, but when building a raised bed try to remove as many as possible. And be sure to amend the soil with compost to make the soil looser so the roots stay straight. If your soil is heavy clay or a rock jungle, try growing round varieties such as ‘Thumbelina'.
For easier germination of small carrot seeds, try purchasing pelleted seeds. These seeds are covered with a biodegradable coating, making the seed larger and easier to handle. However, the seed germination isn't affected. Sprinkle carrot seeds on the top of the soil and then cover them with a thin layer of potting soil or sand. Potting soil and sand are lighter than garden soil, enabling tender seedlings to more easily grow through.
Keep your soil moist. If it dries, the seedlings can quickly die. (See Chapter 15 for more on watering.)
Grow carrots as a fall crop, starting 1 to 2 months before your first frost date. They germinate faster in the warmer soil of summer, and their flavor is sweeter when they mature in cooler fall weather. In hot-summer areas, you may need to shade your newly sown soil with a shade cloth; hot soil temperatures hinder proper seed germination. (The appendix has more on frost dates.)
If your carrot tops break off during harvest (some always do), use a garden fork to dig up their roots. Pull the largest carrot roots first to leave room for the smaller roots to fill out. And if you can't eat all your carrots before the first freeze, lay a 6- to 8- inch-thick layer of hay or straw over the carrot bed. This layer of protection will keep the soil thawed, allowing you to go out on a winter's day and harvest fresh carrots right until spring.
If you're really hungry for carrots and can't wait until they fully mature, you can harvest young carrots anytime after the roots have formed. They just won't taste as sweet unless you grow the baby types.
Growing onions
The simplest way to grow onions is from a set or plant. But you can also directly sow onion seeds in spring, 2 weeks before your last frost date, or start them indoors 8 weeks earlier. For a fall planting of onions, start seedlings indoors or buy transplants. Plant the onion plants 4 to 6 weeks before the first frost. If you're starting your own seeds for a fall planting, start them indoors 8 weeks earlier.
If you start onions indoors, keep the plants stocky and short; whenever they get long and straggly, cut the tops with scissors so the plants are 3 inches tall. Trimming encourages better root growth and keeps the plants at a manageable size. Keep the seedlings moist and grow them under lights (Chapter 13 has more on growing seedlings indoors). Then harden off the transplants — gradually introduce them to the outdoor growing environment by bringing them outside for longer amounts of time each day for up to 1 week; then plant them 4 to 6 inches apart.
What makes onions pungent or sweet? The sulfur, not the sugar. Sweet onions have less sulfur than pungent varieties, so they taste sweeter. Even though the sulfur can make the onion more pungent, it also makes those varieties great storage onions. To keep your sweet onions as sweet as they can be, don't apply any sulfur fertilizers. Also keep the onion plants stress free by controlling weeds and making sure that the plants receive enough water and fertilizer (such as 5-5-5). If you do so, they will thrive and be sweet.
You can harvest onions anytime if you want scallions or small, baby onions, but for the largest bulbs, wait until about 80 percent of the tops have naturally started to fall over. Pull the bulbs out on a dry day if possible and then let them dry out in a warm, shady spot. For more on harvesting, see Chapter 19.
Producing potatoes
Potatoes are mostly grown from seed potatoes, which are either small potatoes or larger ones cut so that each piece has two eyes (those small indentations on a potato's skin). Eyes are dormant buds from which roots and shoots grow. Plant pieces about 8 to 10 inches apart in rows.
Don't try to plant potatoes that you purchase from a grocery store. These spuds have been treated with a chemical sprouting inhibitor, so they either won't grow any plants or the plants will be weak and not productive. It's best to purchase seed potatoes from a mail-order catalog, nursery, or garden center.
In this section, I describe essential techniques for growing potatoes.
Protecting your taters with the hilling technique
If you weed your root crop patch, mulch it with hay or straw, and water it well, crisp roots will be yours for the taking in no time. However, potatoes do require one more special technique, called hilling. Hilling is the technique of mounding up the soil with a hoe around the plants as they grow (see Figure 6-2). Hill at least twice during the growing season — about 1 week after the leaves emerge from the soil and again 2 to 3 weeks later. Hilling promotes the production of bigger potatoes and more of them, kills weeds, and keeps the sun off the tubers.
After your final hilling, lay a 3- to 4-inch-thick layer of hay or straw around your potatoes. Not only will this layer reduce the amount of weeding you do the rest of the summer, but it also will keep the soil cool and moist — perfect tuber-forming conditions! This layer also helps create larger tubers with fewer problems, such as hollow heart (when the center of the potato is hollow due to moisture stress).
Figure 6-2:Hilling potatoes encourages more of them to form.
Any direct sun on potatoes causes chlorophyll to form, turning the potato skins green and giving them an off taste. Tubers actually are mildly poisonous after they've formed chlorophyll, but you'd have to eat a truckload to really get sick. Keep the potatoes hilled and mulched when in the ground, and store them in the dark after harvest to avoid this problem. If you have a small green patch on your potato, just cut if off; the rest of the tuber is fine to eat.
Applying a space-saving planting technique
Don't have room in your garden but want to grow potatoes? Instead of planting in rows, try growing potatoes vertically in potato towers (see Figure 6-3). Here's how:
1. Place a 3-foot-diameter heavy wire cage over cultivated soil.
2. Add a 2- to 3-inch layer of soil to the bottom of the cage, and line the sides of the ca
ge with hay. Plant four seed potatoes in the bottom of the cage and cover them with soil.
3. As the potato plants grow, continue adding soil over them and adding hay around the inside of the cage until you reach the top of the tower. Keep the soil well watered.
4. In the fall, open the cage and watch your tubers roll out!
Digging up the fruits (er, vegetables) of your labor
Harvesting potatoes is like going on an archeological dig. After a potato plant dies, use a metal garden fork and dig up the area 1 foot away from the row so you don't spear the tubers. You'll be amazed at the number of tubers you find — on average, 10 to 20 per plant. Dry the potatoes for an hour or so in the shade, and then store them in a dark, airy, 60-degree area for curing (the process of letting the skin toughen so the vegetables store better). After 2 weeks, move the potatoes to a shed or room that's 40 to 50 degrees to store for up to 9 months (depending on the variety). Always eat any damaged tubers first, because they'll be the first to rot in storage.
Figure 6-3: You can grow potatoes in towers if you don't have much room in your garden.
New potatoes are just young potatoes, and with their soft skin and texture, they make a great summer treat. If you can't wait until the main harvest is ready, steal a few new potatoes the second time you hill. Just reach into the soil and feel for small, round tubers. Taking a few won't kill the plant, and you'll still get some larger spuds later on.
The sweetest of tubers: Planting sweet potatoes
Sweet potatoes (Ipomoea batatas) are a root crop with a reputation for being grown only in the South. However, if you choose the right varieties, you can grow sweet potatoes just about anywhere — even in cold climates like Minnesota. Sweet potatoes are easy to grow and store well indoors in winter. The orange- or yellow-fleshed tubers can be baked, mashed, or sliced and deep fried for a nutritious and delicious snack. Some short-season varieties (90 days) to grow are ‘Beauregard', ‘Centennial', and ‘Georgia Jet'. Other varieties that mature 1 to 2 weeks later are ‘Bush Porto Rico', Jewel', and ‘Vardaman'.
To grow sweet potatoes, you don't plant seeds. Instead, you buy small plants called slips. Slips are available at local nurseries or garden centers in spring or through the mail. You can start your own at home, but it's better to purchase certified disease-free slips from commercial growers to avoid disease. Sweet potatoes love the heat, so wait until the soil temperature is at least 60 degrees before planting. The vines of your sweet potatoes will create a dense, mat-like groundcover, making this an attractive and edible plant to grow.
To plant and grow your sweet tubers follow these steps:
1. Create raised beds at least 6 inches tall and amend the soil with compost.
2. Plant the slips up to their bottom leaves, 1 foot apart in the raised beds.
In cold-winter areas, consider laying black plastic over the beds, punching holes, and planting the slips through the plastic so the soil will heat up faster and the tubers will grow and mature sooner.
3. Side-dress the plants once, a month after planting.
When side-dressing, use an organic fertilizer, such as 5-5-5, or a mix of blood and bone meal fertilizer. And be sure to keep your plants well weeded and watered. Keep the soil on the slightly acidic pH side to avoid some diseases. (Check out Chapter 15 for details on side-dressing and fertilizing.)
4. Before the first frost, or about 100 days after planting, dig under the plants and check for roots.
Pull plants that have formed good-sized roots and cure (dry) these in a warm (80-degree) room for 2 weeks. The curing process not only helps the skin toughen, but also converts starches to sugars, giving sweet potatoes their characteristic taste.
After curing, eat the tubers or store them in a humid, 55-degree basement (or in any other cool area of your house) all winter.
Keeping Your Root Crops Healthy and Pest-Free
Many of the same pests and diseases that you find on other vegetable crops — such as aphids, flea beetles, thrips, mosaic virus, and nematodes — also occur on root crops. Other potentially damaging root crop pests are animals — such as rabbits, mice, and chipmunks — that enjoy the underground snacks out of sight of predators. I lost most of my potato crop one year due to an overpopulation of hungry chipmunks looking for food. (I discuss insect and animal pests as well as common diseases in more detail in Chapter 17.)
Check with your local Cooperative Extension Service office or the folks at your local nursery or garden store to find out what specific diseases and insects may be problems in your area. Then, as with any vegetable, you can plant varieties that are resistant to those diseases and insects.
Besides the usual suspects that attack vegetable gardens, a few pests and diseases specifically harm root crops. Here are descriptions of them as well as the appropriate controls:
Blight: This fungal disease can wreak havoc on potatoes. Late blight, in particular, is the infamous disease that destroyed potatoes in Ireland in the 1840s, causing the Irish potato famine. This disease thrives in cool, humid weather, and infection starts in the form of water-soaked black spots on the leaves.
Unfortunately, once blight starts, you can't treat it; the plants can die, and any tuber that they produce also may be infected and inedible. To avoid this disease, mulch, rotate crops, pull up any volunteer potatoes that sprout from old tubers in the ground, and plant certified disease-free seed potatoes.
Carrot rust fly: If your carrots' roots have holes bored into them, they may be infected with carrot rust flies. The adult flies lay their eggs on the soil near carrot plants, and then when the young larvae hatch, they tunnel into the soil to feed on the carrot roots. If your carrots have these holes in them, you can eat the carrots as long as the disease hasn't started rotting the root.
To avoid this problem, rotate crops, grow resistant varieties, and cover the plants with a floating row cover (a cheesecloth-like material that lets air, water, and sun in, but keeps bugs out; see Chapter 21).
Colorado potato beetle: The most destructive potato pests, these 1/2-inch-long, tan- and brown-striped adult beetles lay yellow eggs in clusters on the undersides of potato leaves, starting in early summer. After the eggs hatch, the dark-red larvae feed on the leaves and can quickly destroy your crop (see Figure 6-4).
Figure 6-4: Colorado potato beetle eggs, larvae, and adults love potato leaves.
Control these insects by growing resistant varieties, crushing their eggs on sight, handpicking the young beetles, mulching with a thick layer of hay to slow their spread, and spraying the biological spray Bt ‘San Diego', which is specifically designed to kill young potato beetles but doesn't harm other insects, animals, or people, on the larvae. Potatoes can withstand significant potato beetle leaf damage and still produce. You just won't receive as large of a crop.
Onion maggot: This pest's larvae attack the bulbs of developing onions, causing holes, opening the bulb to infection from disease, and making them inedible. Onion maggots like cool, wet weather. To control onion maggots, place a floating row cover over young seedlings after the weather warms to around 70 degrees. Doing so prevents the adult flies from laying eggs on the young plants.
Potato scab: This fungal disease causes a potato's skin to turn brown with a corky texture. Tubers with potato scab are unattractive but still edible. Control this cosmetic disease by planting resistant varieties and rotating your crops.
Wireworm: These jointed, hard-shelled, tan-colored, 1-inch worms feed on underground tuber roots as well as the bulbs of a number of crops. They're generally a problem with recently sodded soil. Control this pest by setting potato traps before your root crops begin maturing. Spear a potato piece on a stick and bury it 2- to 4-inches in the ground; the wireworms should infest the potato piece. Dig up the piece after 1 week and then destroy it.
Chapter 7: Sweet and Simple: Beans and Peas
In This Chapter
Growing bean and pea varieties of different heights, colors, and flavors
Planting bea
ns and peas in your garden
Caring for your beans and peas
Harvesting your crop
One vegetable that you can always rely on is the bean. So for ensured success in your first garden, plant some bean seeds. When I teach gardening to beginner groups, the first plants that I talk about are bean plants — and for good reason. Bean seeds are large and easy to plant, they grow easily, and they don't require lots of extra fertilizer or care. Within 60 days, you're bound to have some beans to eat. With beans, satisfaction is as guaranteed as it gets in the vegetable gardening world. In fact, they're even more forgiving than tomatoes!
Peas are in the same legume family as beans; other crops in this family include clover and alfalfa, but you don't eat them (unless you grow sprouts!). Like beans, peas also have large seeds and require little care. The only difference between the two is that peas like cool weather to grow and mature, whereas beans like it warm. If you get the timing right for beans and peas, you'll have lots of legumes rolling through your kitchen door; just use the guidelines in this chapter to get started. (See the appendix for a general planting guide for selected beans and peas.)
A Bevy of Beans: Filling Your Rows with Bean Family Plants
All bush, pole, and dried beans are members of the Fabaceae family. In this section, I classify beans according to their growth habits and usage (that is, whether you eat them fresh or dried). Here are the categories: