Not only does the Rakkyo have certain preferences regarding how much water it receives, but it also cares deeply about how you provide that water. In fact, if you don't use the proper watering technique, you risk harming your tomatoes. The best way to water Rakkyo is to apply the water directly to the soil in a slow and gentle manner. You should not pour all of the water into the soil at once, and you should not do overhead watering for your Rakkyo. Although you should water slowly, you should also water deeply to ensure that all of the soil in which your Rakkyo grows is sufficiently moist.

If you find that you have overwatered your Rakkyo and you are concerned about the associated risk of disease, you should intervene immediately. Often the best approach for an overwatered Rakkyo is to uproot it from its current growing location. Once the plant is out of the ground, you can allow its roots to dry a bit before planting it in a new growing location. Ensure that the new growing location has soil with good drainage. If you grow in pots, you may also want to move your plant to a pot with more or larger drainage holes. In the case of underwatering, all you will need to do is increase the frequency with which you supply water to your plant.

Overall, Rakkyo requires a significant amount of water throughout the growing season. To meet that high water need, you'll need to water early and often throughout the spring and summer. During the earlier parts of the growing season, you should water your Rakkyo about once or twice per week. As the season progresses, you should increase your watering frequency. You may need to water it twice per day or more during summer, depending on the weather. After your Rakkyo have gone through their major seasonal growth phases, you can reduce the frequency of your watering to about once per week until the end of the growing season.

Since Rakkyo are incredibly popular, with many professional and amateur gardeners growing them successfully, we have a pretty clear idea of how to care for these plants. That understanding includes specific knowledge about the precise volume of water an average Rakkyo should receive. Generally, Rakkyo will require about 1 - 1.5 inches of water per week. That volume should be dispersed evenly through your weekly watering. As the weather gets warmer, you may need to supply more water, but in most cases, two inches per week is a good baseline amount.

Underwatering and overwatering can both occur as problems for your Rakkyo, and both these problems can manifest with similar symptoms. For example, foliage discoloration and wilting can both result from either overwatering or underwatering. When your Rakkyo is underwatered, its leaves will be curling and drooping at the beginning. You will see a bunch of leaves turn less vigorous. Underwatering is also likely to cause stunted growth and poor overall development as both the flowers and this plant require a high amount of water. Overwatering is more likely to lead to disease, including rot. Overwatering may also lead to unpleasant smells rising from your plant's soil. The symptoms of underwatering will show up quicker than overwatering. Overwatering can also be evident in soil conditions. Mainly, if you notice a lot of standing water or waterlogged soils, overwatering is likely to occur.

As alluded to above, your Rakkyo's water needs will repeatedly change throughout the seasons. During most of spring and summer, you should water your Rakkyo about once every week. As the heat of summer arrives, you should plan to increase your watering frequency to once or twice per day. In the late summer and fall, towards the end of the harvest period, you can reduce your watering frequency to about once per week. After harvest has ended, you can cease watering as your Rakkyo has reached the end of its life cycle and will require no further soil moisture. The maintenance schedule of Rakkyo will require you to alter the amount of water you provide depending on the plant's current growth stage. Early on, especially if you grow your Rakkyo from seeds, you'll need to provide water often enough to maintain consistent soil moisture, which encourages root development. When the plant becomes old enough to produce flowers, it will likely need even more water. During the fruit development growth stage, your Rakkyo will likely need the most water out of any growth period, at times requiring water more than twice per day. Following that phase, the water needs of Rakkyo will decline significantly.

Whether you grow Rakkyo indoors or outdoors can also play a role in how you water them. Rakkyo that grows outdoors may receive water from natural rainfall, which will reduce the amount of supplemental water you should supply. However, it is incredibly rare for rainfall to adequately replace your watering entirely. Plants that grow indoors, along with any Rakkyo that grows in a container, will need to be watered more frequently than those that grow in the ground outdoors. If you choose this route, please make sure that the plant gets enough water by checking the soil moisture within your pot often to keep your Rakkyo healthy.

You can prune your Rakkyo any time you notice dead, diseased, or damaged leaves during the growing season. Once you notice such a leave, locate an unwanted leaf, then follow its stem all the way to the bottom of petiole. Removing dead stems will increase the light and ventilation of the plant and help it to grow. You can cut its stem just above the soil’s surface to remove it. Such pruning can take place as needed during spring and summer. Also, this plant can bloom any time between spring and fall, and some gardeners choose to remove flower buds before they have a chance to open. Removing unopened flower buds allows this plant to focus most of its growing energy on its beautiful leaves. However, pruning in this manner does not necessarily influence the plant’s overall health. Cutting back should be done late in the winter to early spring. Ideally, you should wait until you see new basal growth before you cut off the dead and dried winter parts, to about 6 inches from the ground.

Pruning the Rakkyo is as easy as waiting until you notice dead or damaged leaves on your plant. When you recognize these leaves, equip yourself with a pair of sharp and sterile hand pruning shears. Hand pruning shears will work best as larger tools like loppers will not be well suited to the precise cuts you need to make. Once you have a proper set of pruning tools, locate an unwanted leaf, then follow its stem all the way to the bottom of petiole. Removing dead stems will increase the light and ventilation of the plant and help it to grow. Cut the stem just above where it exits the soil to remove it entirely. If you wish to stop this plant from flowering, you can use the same pruning shears to remove any buds before they open. Finally, you may prefer to just trim off dead or damaged portions of the plant, including deadheading spent flowers, to keep it looking its best. This can be done at any time of year. Diseased or damaged stems should be cut right at the soil line and removed completely. Blooms should be cut off just below the flower head. Cutting back should be done late in the winter to early spring. Ideally, you should wait until you see new basal growth before you cut off the dead and dried winter parts to about 6 inches from the ground.

All that is required of you once you have pruned your Rakkyo is to clean up. Once you have pruned, deadheaded, or cut back your Rakkyo, gather the bits you have cut off and discard them. If there are any diseased parts of the plant that you have pruned away, do not discard them with the rest of the pruned pieces. Diseased foliage should be disposed of. When watering after pruning, be careful not to touch the wound to prevent fungus from infecting the plant through the fresh wound. Placing Rakkyo in a well-ventilated location will also help the wound to dry out and heal in time.

For your major pruning, use sharp pruning sheers that will make clean cuts to avoid damaging your plants. As you are pruning your Rakkyo, step back occasionally to check the appearance of the plant to make sure it has the shape you want and that you are pruning it symmetricaly. It is recommended that gloves and safety glasses be worn while pruning Rakkyo.

Pruning is an important part of plant care and maintenance. Different plants have different pruning requirements. Some plants may need little to no pruning, while others may require more specific attention. Most plants should be pruned to remove damaged or unhealthy foliage. Other plants may be pruned to control their shape and size. Pruning may even be done to remove the flower heads of plants and stop them from self-seeding. Although some gardeners may find pruning a tedious task, it is a necessary evil and is an essential part of keeping your plants happy and healthy.

Exact needs vary, but a minimum of 6 to 8 hours per day is a good rule of thumb for Rakkyo to grow and produce fruit.

Rakkyo requires full sun, meaning that it should be grown in a location that gets direct sunlight that isn’t blocked by obstacles such as trees, fences, or buildings. In general, the faster the plant grows, the more hours of sunlight it will need. Morning sun is best for photosynthesis.

Rakkyo should not need to be protected from the sun in most climates. Those who live in a desert or near the equator may find that the sun is too harsh for the types of plants they want to grow, but this is the exception.

All plants need sunlight to convert into energy. Plants that have a short growing season need even more light and energy than those that grow slowly, as they need to complete all their processes to grow and produce fruit within just a few months. The first symptoms of insufficient sunlight in Rakkyo are pale and yellow leaves that are not able to generate enough chlorophyll to keep their healthy green color. The leaves may eventually fall off, and new growth is small and weak. The plant may become leggy and sparse as it stretches toward the available light. Finally, without enough light the plant will not be able to produce large, high-quality edible leaves or fruit. Rakkyo needs to devote a lot of energy into growing leaves and fruits, so if there isn’t enough light available for it to convert, the harvest will suffer.

Rakkyo can get sunburned from intense sunlight, especially when coupled with high temperatures and not having enough water. Afternoon sun tends to be most likely to burn plants. Scalded leaves develop faded patches of light brown to white on the areas at the top of the plant that are exposed to the most sun. They are especially vulnerable to this right after being transplanted from a shadier location to being in full sun. Transitioning plants gradually or providing them with a barrier while they are adjusting can help prevent sunscald in young plants. In many cases, Rakkyo develops leaves that are large enough to protect fruits from the strongest rays of the sun. However, if intense sunlight is in contact with fruits, they can also be damaged. Avoid over-pruning those protective leaves so that the fruits don’t get burned.

Rakkyo may become unbalanced if it gets significantly more light on one side than the other. Ideally, you can plant your Rakkyo in a location away from obstacles that might block light, and where the distribution of sunlight is even on all sides. Be careful about planting tall species next to those that grow closer to the ground. It may not be obvious when the crops are first planted, but over time the taller plants may begin to block the amount of sunlight that can reach the shorter plants. Morning sun helps to dry dew and precipitation, which helps prevent infection from diseases that can develop when water sits on the plant. If you are watering or irrigating your Rakkyo, this should be done in the morning.

There is an ideal temperature range that makes Rakkyo feel at home. Under these temperature conditions, it's unlikely that you’ll have any issues with cold or hot damage to the foliage, but changing leaf colors can absolutely be a sign that Rakkyo isn’t happy. Try to keep your Rakkyo well within its preferred range of 70-85℉(21-30℃), but don’t panic if the temperature creeps up past 85℉(30℃) during the day or down to 70℉(21℃) at night.

If your Rakkyo happens to be planted outside, then there’s not much you can do to try to move it indoors. However, you can certainly provide cover in ways that will help it survive any extreme temperatures that may arise unexpectedly. For instance, you can always use a few stakes and some cloth to put together a shade tent that will block out much of the sun’s intense heat from direct sunlight exposure. Similarly, Rakkyo can be protected from the extreme cold and especially chilly winds by building a small greenhouse around the plant, which will create a greenhouse effect and warm the plant up. This can be done using garden stakes and any sort of clear or translucent plastic you may have around; if you have greenhouse plastic such as polycarbonate laying around, this works perfectly. Remove the greenhouse once temperatures warm up to 40℉(10℃) at night.

Generally speaking, Rakkyo needs to stay within its preferred temperature range all year long. However, that doesn’t mean that care should stay the same all year long. During the warmest months of the year, Rakkyo will need a little extra shade and a bit more of a breeze to help it cope with the hottest days. On the other hand, it may need to be moved away from chilly windows and doors during the cooler months in climates where temperatures drop below 40℉(10℃) at any point in the year.

Keeping your Rakkyo at the right temperature can be fairly simple. Depending on where you grow it, Rakkyo can be fairly easy to accommodate. For indoor growing, you can easily move the plant to different locations within your indoor space that best meet its temperature requirements. Avoid placing it near air conditioning vents, heaters, doors that open frequently, or drafty windows. It is a little more difficult to control the temperature around your Rakkyo if it’s grown outside. Of course, if it’s planted in a pot, you can simply bring it indoors when the temperatures outside get too hot or too cold for Rakkyo, but otherwise, you may need to take different measures to protect it from extreme heat or cold that may damage it irreversibly. Try placing Rakkyo under cover to protect from both the harsh sun that can overheat it and any cold wind that could be potentially deadly for your plant.

You may or may not need to fertilize your Rakkyo, depending on the soil conditions in your garden. If you are able to get a good harvest from your Rakkyo crop, that is a good indication that fertilizer isn't necessary. However, the best way to determine whether or not you need to fertilize is by having the soil tested. You can test soil yourself using a kit, or you can send the soil out to a lab to be analyzed. Once you have an understanding of the nutrient levels in your soil, it will be easier to determine whether or not additional fertilizer is required.

Mix a layer of organic fertilizer into the soil at least a week prior to planting, and use another dressing on top of the soil during the spring to provide an extra boost to young plants. In most cases, just one to two applications of fertilizer during a growing season should be sufficient for a good harvest of Rakkyo.

Fertilizing a Rakkyo after the majority of the vegetables have been harvested will be a waste of your fertilizer and your energy, since this crop needs to be replanted every year. Also avoid fertilizing Rakkyo if you are already gardening in a location that has nutrient-rich soil. Since Rakkyo does not require a lot of fertilizer to grow well and yield plenty of vegetables with good size and flavor, there is no need to fertilize in many cases. Only fertilize your Rakkyo if your soil test indicates that one or more nutrients is lacking in your garden soil.

The best option for Rakkyo is a natural organic fertilizer, but slow-release granular fertilizers also work well. A low-nitrogen fertilizer is best, since too much nitrogen can cause excessive foliage production that takes away from the plant's ability to produce strong root vegetables. Use a formula with lower nitrogen such as 5-10-10 to make sure that the plant develops a good harvest. Organic mulch is also recommended for growing healthy Rakkyo. A layer of mulch made from leaves, straw, grass clippings, or other organic matter helps phosphorus to prevent weeds, keep the soil moist, regulate soil temperature, and release a slow but steady supply of nutrients into the soil as the mulch breaks down.

Spread organic fertilizer such as manure or compost in a thick layer across the bed prior to planting, then mix or till the amendment into the soil. Additional organic fertilizer can be added on top of the soil after planting, in a layer about two to four inches thick. After adding any type of fertilizer, be sure to water thoroughly. When using chemical fertilizers, be sure to follow all manufacturer's directions to achieve the best results and avoid adding too much fertilizer to the garden. All types of fertilizer should be applied to the soil around the plant but not in contact with the plant itself, since contact with fertilizer can burn the plant's tissues.

The most typical scenario that occurs when Rakkyo is overfertilized is that the plant receives too much nitrogen, which is out of balance with other nutrients. Rakkyo is grown for its roots and not for its leaves, but nitrogen mainly supports the healthy development of foliage. For that reason, giving a Rakkyo plant too much nitrogen can cause it to develop a lot of foliage at the expense of the tubers that gardeners want. Phosporus is the nutrient that helps to promote root development, so it is important that Rakkyo be given plenty of phosphorus in addition to other required nutrients in order to yield plenty of vegetables.