Vegetable Gardening Page 26
As your plants get sturdier, you can water with a sprinkling can that has a rose, a nozzle that breaks the water into many fine streams. After the plants grow their first set of true leaves (the first leaves to open as the seed germinates are called seedling leaves, and the next set are true leaves) and have a bigger root system, let the soil dry out slightly between waterings.
Give the plants enough water at one time so that some of it runs out the drainage holes in the bottom of the container, but never leave the container sitting in water. Overwatering promotes damping-off disease (see the sidebar "Dealing with damping off") and decreases the amount of air in the soil, resulting in a weaker root system.
With soilless mixes, you may have a difficult time deciding when to water, because the soil looks dry on the surface even though plenty of moisture is still present. To check whether the soil has moisture, take a small amount of soil off the top 1/2 inch of mix and squeeze it between your fingers. If you can squeeze out any water, hold off watering. The difference in a container's weight when the soil is moist compared to when it's dry can also indicate when to water. Dry soil is very light. Finally, wilted seedlings also are a sure sign that you've waited too long to water (unless, of course, your plants have damping off).
Certain types of containers require more frequent watering. For example, soil in clay pots dries out faster than soil in plastic pots. Peat pots dry out fast and are difficult to rewet. Try putting your peat pots or growing-cubes in a tray and packing moist peat moss between them to keep them from drying out too quickly.
Self-watering seed starting kits that reduce the need for checking your seedlings daily for dryness are now available. These kits have a reservoir of water in the bottom of the tray that wicks into the pots when the soil is dry. See the appendix for companies carrying seed starting supplies.
Thinning and transplanting indoors
After seedlings develop their first set of true leaves (or when onions or leeks, which send up a single blade, are 2 inches tall), you need to thin them or move them from shallow flats to larger quarters. Thinning is an important step, and timing is crucial. If you let your seedlings grow too large in a small container, their growth is stunted. And if you don't space them out at all, you end up with weak plants.
To thin plants that will continue growing in the same container, snip out extra seedlings at the soil line with a pair of scissors, as shown in Figure 13-2. If you try to pull these seedlings out, you may disturb the roots of the plants that are staying. Also be sure to snip out any weak or misshapen plants. The appendix explains how much space to leave between different types of vegetable seedlings.
To move seedlings to a new container, first fill a larger container (plastic six-packs, 4-inch pots, or peat pots) with moist potting soil. Poke holes in the soil large enough to put the seedling roots in — the eraser end of a pencil is a good tool for this. Dig around the plants carefully by using the blade of a table knife or a small stick, such as a plant label, and then lift the seedlings out of the soil. Always hold the seedlings by the tips of their leaves; otherwise, you can easily crush their delicate stems or injure their growing tips. Set the plants in the new container, slightly deeper than they were growing before. Firm the soil gently around the roots, water well, and keep the plants out of direct sun for a day or two until they adjust to their new pots.
Figure 13-2: Thin seedlings at the soil line with scissors.
Feeding your seedlings
Regular fertilizing helps produce strong, healthy plants. Some potting soils already have fertilizer mixed in, and in that case you don't have to add more. For other types, use a diluted water-soluble fertilizer to one-third strength (usually 1 teaspoon of fertilizer per gallon of water) to water your seedlings. Water with the solution once a week. For more on fertilizers, see Chapter 15.
Dealing with damping off
One day you're admiring your strong, healthy seedlings, and the next day you're gaping in dismay at the sight of them toppled over and dying. The attacker is called damping off, which is a fungus that infects young seedlings, sometimes even before they have a chance to emerge from the soil. If you examine infected seedlings closely, you usually can see that part of the stem near the soil line is sunken, shriveled, and water soaked. Sometimes a white mold also forms on the stem.
Damping off is one of the most common problems that seed-starters face, but fortunately you can control it with good sanitation and cultural practices (proper watering, fertilizing, and lighting). Sterilizing containers with a bleach solution and using sterile potting soil go a long way toward preventing problems. Wet potting soil and high nitrogen encourage this fungus, so avoid overwatering, and use a well-drained germinating mix that's low in nitrogen. Or consider using fertilizer only after the seedlings develop their first true leaves. Sowing seeds thinly to allow good air circulation also can help. Many seeds come coated with a fungicide that helps prevent damping off.
If you notice seedlings in one portion of a container beginning to wither, cut them off and remove the soil around them as quickly as possible. Then do whatever you can to make conditions less favorable for the fungus (basically, let the soil dry more). With luck, you'll be able to save the rest of the batch.
Transplanting Indoor Seedlings and Starter Plants
After you nurture your seedlings indoors for a good 4 to 8 weeks, and when the weather's right for planting (see Chapter 3 to find out when to plant in your area), you're ready to transplant the seedlings outdoors. Or maybe you haven't grown seedlings at all, but you want to buy some starter plants at a nursery and get them in the ground. I discuss both scenarios in the following sections.
Buying starter plants
If you don't start your transplants from seeds at home, you can buy them at a nursery or garden center. You can find seedlings of almost every type and size around planting time. However, the range of varieties available will be greater if you start your own transplants from seed.
Follow these tips when buying starter plants:
Choose healthy-looking plants. Tomatoes, for example, should have a stocky stem, be about 4- to 6-inches tall, and sport dark-green foliage. Read the Part II chapters that discuss the vegetable you want to find out what makes a healthy-looking plant.
Avoid large, crowded, spindly plants in small containers. The roots of these types of plants are often bound up and have no room to grow. You can check the roots for yourself by gently removing the transplants from their containers (if you aren't sure how to do this, see "Making the big move to the ground," later in this chapter). If you see a dense mat of roots around the outside of the root ball (the soil with roots growing in it), the plants probably have been in the pot too long.
Buy plants at the optimum size. Plants with four to six leaves and short, stocky stems are usually best. In general, younger plants are better than tall, older plants that most likely were stressed at one point or another.
Avoid plants that are already flowering and have fruit on them. Plants with flowers and fruits never produce well.
You can sometimes buy large tomato plants in 1-gallon or larger pots — sometimes they even have tomatoes on them. In my experience, these large plants rarely grow well after you get them home. I prefer smaller transplants that can get off to a running start.
You can buy vegetable transplants locally, but many mail-order seed companies now also offer a wide range of vegetable varieties as small plants or plugs. The plants usually are in good shape. They offer a wider selection than you can find in garden centers, you don't have to drive around to find the best transplants, and they ship plants to you at the appropriate planting time for your region. See the appendix for the addresses of various mail-order companies.
Toughening up all types of transplants
Vegetable seedlings that are grown indoors at home or purchased from a greenhouse or nursery in spring need to acclimate gradually to the brighter light and cooler temperatures of the outside world. This process, called hardening off,
slows plant growth, causing the plants to store more food internally and increase the thickness of their outer leaf layers. Basically, hardening off toughens up transplants for the cold, cruel, outside world.
To harden off your transplants, follow these steps:
1. A week or two before you intend to set plants out in your garden, stop fertilizing and reduce the amount of water you give them.
Give plants just enough water so they don't wilt.
2. Take your plants outside for a short time.
Give the plants a half hour of filtered sunlight — setting them under an arbor or open-branched tree — during the warmest part of the day. If the weather is windy, put the plants in a spot where they're sheltered, or construct a windbreak out of pieces of wood.
3. Gradually increase the amount of time that the plants spend outside and the intensity of the light that they're exposed to.
You want to increase the amount of time your plants are outside so that by day seven, they're out all day. Move them into progressively sunnier locations during the week so they get used to their future condition in the ground. However, make sure that you bring the plants in every night.
Another option is to move your plants to a cold frame (see Chapter 21), and then you can open the cold frame more each day and close it at night. Plants that are raised in a cold frame from the time that they're young seedlings will need much less hardening off.
Don't overharden your plants. Certain crops, such as cabbage and broccoli, can quickly bolt (flower before they're supposed to) if seedlings older than 3 weeks are repeatedly exposed to temperatures lower than 40 degrees for a couple of weeks.
Making the big move to the ground
Before transplanting your homegrown seedlings or nursery-bought transplants, you need to prepare your soil and sculpt beds or rows (as described in Chapter 14), and your garden must be ready to plant. If you're worried about keeping the rows straight, use string and stakes as described in the later section "Row planting."
Choose a calm, cloudy day to transplant, if possible. Late afternoon is a good time because plants can recover from the shock of transplanting without sitting in the midday heat and sun. Your garden soil should be moist, but not soggy. If the weather has been dry, water the planting area the day before you plant. Moisten the soil in your flats or pots so it holds together around the plants' roots when you remove the plants from their containers.
When setting out plants in biodegradable peat pots, make slits down the sides of the pots or gently tear the sides to enable the roots to push through. Also, tear off the lip (top) of the pot so it doesn't stick up above the soil surface and pull moisture out of the soil. If you're using premade growing blocks encased in netting, cut off the netting before planting.
To transplant seedlings, follow these steps:
1. Use a hoe, spade, or trowel to make a small hole in your garden for each seedling.
The hole should be deep enough so the transplant is at the same depth in the ground as it was in the pot (except for tomatoes). Make the hole twice as wide as the root ball.
2. Unpot a seedling (unless it's in a peat pot) by turning its pot upside down and cupping the seedling with your hand.
Be sure to keep the root mass and soil intact. If the seedling doesn't come out easily, gently tap on the edge of the pot or gently press on the bottom of each cell of the flat with your fingers. Whatever you do, don't yank out a plant by its stem.
3. Check the root ball's condition.
If the roots are wound around the outside of the pot, work them loose with your fingers so they can grow out into the soil. Unwind larger roots and break smaller ones (this won't hurt them) so they all point outward. Try to keep as much of the original soil intact as possible.
4. Mix a diluted liquid fertilizer into the soil of the planting hole to help the plants get off to a fast start.
Reduce the recommended strength on the fertilizer container by half. For example, if it says apply 1 tablespoon per gallon of water, use only 1/2 tablespoon. (See Chapter 15 for more on fertilizers.)
5. Put each prepared seedling into the holes that you made.
Most young vegetables should be planted at the same soil level as they were in the pot, as shown in Figure 13-3. For some vegetables, such as tomatoes, you can sink the seedling a little deeper. They grow extra roots along the lower portion of their stems and thrive with this treatment.
6. After firming the soil around the roots with your hands, form a shallow soil basin around the base of the transplant.
The soil basin serves as a moat around the seedling to hold water. When you water or it rains, the moisture stays in the moat and drains to where the roots are located. Chapter 15 provides more information on soil basins.
7. Depending on the conditions, water the bed that day or the next.
If the weather has been dry or if the soil is sandy, you may want to water the entire bed; if it's rainy or the soil is already very wet, wait until tomorrow to water.
8. Keep the bed moist while the seedlings get established and begin to grow strongly.
In extreme hot, dry weather, provide temporary shade for transplants with paper tents or wooden shingles pushed into the ground on the south or west side of the plants.
Figure 13-3: Plant vegetable seedlings at the correct depth.
If you don't get an ideal transplanting day and the weather is hot and sunny, shade the plants until the sun goes down. And don't be alarmed if your plants look a little droopy after you set them out; they'll soon recover. Cabbage seedlings can droop and look almost dead, for example, and be up and growing in a day or two.
Sowing Seeds Directly in Your Garden
Unless you live in an area where summers are really short, some vegetables are better off sown directly in a garden rather than as transplants. Large-seeded, fast-growing vegetables — such as corn, melons, squash, beans, and peas — usually languish if they're grown in containers for even a day or two too long. Plants sown directly in the ground usually surpass these seedlings if both are planted at the same time. (Even if you live in a short-season area, you can help speed new plants along. See Chapter 21 for information on extending your growing season.)
In the following sections, I describe different methods for planting seeds right into your garden and show you how to thin seedlings carefully.
Deciding on a seed-planting method
You can plant seeds in a variety of patterns: single rows, wide rows, beds, raised beds, or hills. The method you choose depends on your climate, your tools, and your taste. You can find out more about these planting methods in Chapter 3. Whichever method you choose, here are a few basic principles to keep in mind when planting seeds:
Make sure that the soil has dried out sufficiently before you work it, and be sure that the soil is warm enough for the seeds that you want to plant. Pea seeds, for example, germinate in soil as cool as 40 degrees, and you can plant them as soon as you can work the soil in spring. Squash seeds, on the other hand, need warmth. If your soil temperature is much below 65 degrees, the seeds are likely to rot in the ground before they sprout. (See the appendix for a list of appropriate soil temperatures for different kinds of seeds.) The best way to determine the temperature of your soil is to use a soil thermometer, which you can buy at a garden store. Chapter 14 provides more information on preparing your soil for sowing.
Immediately before planting seeds, loosen your garden soil with a hoe or shovel to a depth of 6 inches. Rake over the area to create a smooth planting surface. Don't walk over areas where you'll be sowing seeds; stay in the pathways. Compacting the soil makes it difficult for seedlings to emerge and send down their roots.
Sow seeds at the proper planting depth. A seed planted too deeply uses up its supply of stored nutrients before the seedling can push its way to the surface; a seed planted too shallow may dry out. A general rule is to plant seeds to depths that are two to three times their diameters, but the appendix gives recommended planting depths for di
fferent kinds of seeds. Also try to sow at a uniform depth because seedlings are more likely to emerge at the same time, enabling you to see where your plants are when you do your first weeding.
Water newly planted seeds carefully. Use a watering can with a rose (nozzle with multiple holes) or a hose with a breaker attachment (a nozzle that breaks the stream into a gentle spray). A strong stream of water can wash seeds out of a bed or too deeply into the ground. Keep the seeds moist but not soggy until the seeds germinate. Heavy soils often form a crust as they dry out, making it difficult for the seedlings to break through. A moist surface helps prevent crusting, as does covering seeds with vermiculite or sand, instead of soil alone. If the weather is dry after you sow the seeds, gently water the seeded area every 2 days or so.
The following sections explain the basic methods for planting your seeds.
Row planting
The first step when row planting is to mark the placement of a row within your garden. A planting line consisting of a simple string and stakes enables you to easily lay out rows. Make a furrow, or trench, at the correct depth along the row. To make a shallow furrow, lay a rake or hoe underneath your string marker, and press the handle into the soil. You can make deeper furrows (ones that can be used for watering, too) by dragging the corner of your hoe across the soil surface, using the string as your guideline.
Sow seeds more thickly than you want the final spacing of the crops to be to ensure an adequate number of plants; some seeds may fail to sprout. Thinning rows is less of a chore if you space seeds as evenly as possible. Large seeds like peas and beans are easy to space at precise intervals, but evenly spacing small seeds can be a real challenge.