Radishes. These fast-growing root crops thrive in soil with a pH between 4.5 and 5.5. Plant them in early spring or fall and give them full sun, consistent water, and well-draining soil. Harvest them when they’re young, because larger radishes become woody and hot.
Radishes tend to bolt to flower and seed as the days get long. (Conversely, they must have at least six hours of sun each day, or they will grow only tops and no bottoms.)
If you want big radishes, plant them deeply, about an inch and a half deep. Planting radishes shallowly -- a half-inch deep -- results in small roots.
A favorite trick is to mix radish seeds with those of carrots or parsnips to mark the rows and help break the soil for these slow-germinating crops. Parsnips and carrots can take up to three weeks to sprout, by which time the radishes will be ready to eat.
If you miss a harvest and the radish roots have become spongy, you might leave the radishes in the ground until they bolt. Shortly after the yellow or white flowers fade, the radishes will produce seed pods, which look like tiny okra pods. Radish seed pods, picked when they are soft and green, are spicy, crunchy and nifty in a salad.
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You can make more radishes from radishes by replanting the root. Other parts of the radish will not regrow if you plant them again.
Step 1
Cut the radish 1 inch from the root end using a kitchen knife. Collect the root ends for planting. The radishes should be cut before harvest to provide the largest roots for regrowth.
Step 2
Cover the entire cut surface of the radish root in germination gel. Spread the gel over the surface evenly using your fingers.
Step 3
Dig a hole 2 inches in the soil using a garden hoe. Place the root end into the hole and cover the hole with soil.
Step 4
Dig a row of holes 2 inches apart from each other. If you dig another row, space the row 10 inches from the previous row.
Step 5
Store the other radishes for future use.
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The top of a common radish (Raphanus sativus) will regrow greens but not a bulb. This annual vegetable is most often used as a root vegetable, yet the tops work well as salad greens and are high in vitamin C. You can grow a new radish from part of an old radish, only not with the top.
If you cut the top off a radish and put it in water, it will generally produce more greens, but it won't create an edible radish. Cutting off the tip with the roots and planting it in moist, fertile soil might result in a new radish plant. For best results, take root cuttings by cutting off the point and roots when harvesting radishes. Another option is to plant the smallest, firmest radishes in the garden. They will probably grow to full maturity, flower and seed. You can grow new radishes by collecting the seeds.
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Lettuce has similar needs, so I often grow the two vegetables in adjacent rows.
Radishes are not without their problems. Flea beetles make tiny holes in the leaves, slugs and snails chew grooves in perfect roots, and a sudden deluge can cause radishes to split and start rotting. These are but a few of the reasons to promptly harvest radishes that have popped up out of the ground, trim off their tops, and store them in the refrigerator.
Despite claims that some radish varieties will hold in the garden without becoming pithy, the truth is that many bad things can happen to radishes that are left unharvested a day or two too long. It is a paradox that while perfect radishes must be promptly harvested, the trimmed roots will store in the refrigerator for months.
growveg
One of the radishes had been topped–the leafy part cut off. It’s the one on the right above. You can see it growing new leaves. The other radish had it’s root cut off.
The radishes were just beginning to blossom when I moved them from California to Washington.
Little pods grew where the blossoms had been pollinated.
thishappyhomestead
How to Save Radish Seed Most radish varieties are annuals that will flower and produce seed within one growing season. They are insect-pollinated out-breeders, meaning they will cross with any and all varieties of wild and domesticated varieties. Varieties should be separated by 1/2 mile or more to prevent cross-pollination. If distance or isolation is not possible in your own garden plant a single variety, and be aware if neighboring gardens have different radish varieties flowering at the same time.
seedsavers
You can plant radishes with other leaf crops, but they shouldn’t follow cabbages, since the two are susceptible to the same maladies.
Get rid of problematic bugs. Fungi aren't the only things that can cause problems with your radishes. Certain bugs can get into your plants and feed on them so that they begin to die. Many times you can avoid these bugs by keeping your garden clear of plant debris and weeds. If they do show up there are some ways you can deal with them.
If your leaves are looking faded and you find that there are tunnels and grooves in the roots, you might have root maggots. These tiny critters are small, gray/white, legless worms. Flies lay their eggs in the soil beside the plant. To get rid of them, add lime or wood ashes to the base of your radish plants. Wait to plant your radishes until the weather is drier so that you avoid the maggot's life cycle.
If you have tiny holes appearing in the radish leaves, you might have flea beetles. These little critters are bronze or black beetles 1/16th of an inch long. If you find you have these, spread diatomaceous earth, a type of soft, sedimentary rock that crumbles easily into a fine, off-white powder. This can act as a natural bug killer.[9] You should also cultivate the ground often, so that you disrupt the beetles' life cycle.
If your radish plants have whitish or yellowish spots, have deformed leaves, or if the plants are wilting, you might have Harlequin bugs. These bugs, which are black with yellow or red or orange markings, suck the fluids out of the radish's plant tissue. Pick out and destroy all the bugs and the egg masses. To help keep them out of your garden, keep it clear of the places where bugs breed, like crop residue and weeds.
If the leaves of your radish plant turn a dull yellow, if they curl and become brittle, your radish plant might have contracted Aster yellows, a mycoplasma disease spread by Leafhoppers. If this is the case, remove the infected plant or plants, and control the leaf-hopper population by keeping down the weeds and plant debris -
wikihow
Radishes can be useful as companion plants for many other crops, probably because their pungent odour deters such insect pests as aphids, cucumber beetles, tomato hornworms, squash bugs, and ants.[15] They can also function as a trap crop, luring insect pests away from the main crop.[16] Cucumbers and radishes seem to thrive when grown in close association with each other, and radishes also grow well with chervil, lettuce, peas, and nasturtiums. However, they react adversely to growing in close association with hyssop. -
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pennington