Allium rosenbachianum is a native of central Asia. It has orange bulbs from which large ball shaped deep purple flowers bloom at the end of a 3 foot stem in May and June. Allium is a bulbous plant with linear leaves and blooms in flowers with umbels on the top of a sturdy stem. Several of the species have foliage which is unpleasant smelling. They will not release their small unless they are walked on.
Google Plant Images: click here!
Where can you buy this plant: click here!
Size: Height: 0 ft. to 3 ft.
Width: 0 ft. to 0 ft.
Plant Category: annuals and biennials, bulbous plants, ground covers, landscape, perennials,
Plant Characteristics: columnar, edible flowers, low maintenance, seed start, spreading,
Foliage Characteristics: fragrant, medium leaves,
Flower Characteristics: erect, long lasting, showy, unusual,
Flower Color: purples,
Tolerances: deer, rabbits,
Bloomtime Range: not applicable
USDA Hardiness Zone: 4 to 10
AHS Heat Zone: Not defined for this plant
Light Range: Part Shade to Part Sun
pH Range: 6.5 to 7.5
Soil Range: Sandy Loam to Loam
Water Range: Normal to Moist
FertilizingHow-to : Fertilization for Young Plants
Young plants need extra phosphorus to encourage good root development. Look for a fertilizer that has phosphorus, P, in it(the second number on the bag.) Apply recommended amount for plant per label directions in the soil at time of planting or at least during the first growing season.
How-to : Fertilization for Established Plants
Established plants can benefit from fertilization. Take a visual inventory of your landscape. Trees need to be fertilized every few years. Shrubs and other plants in the landscape can be fertilized yearly. A soil test can determine existing nutrient levels in the soil. If one or more nutrients is low, a specific instead of an all-purpose fertilizer may be required. Fertilizers that are high in N, nitrogen, will promote green leafy growth. Excess nitrogen in the soil can cause excessive vegetative growth on plants at the expense of flower bud development. It is best to avoid fertilizing late in the growing season. Applications made at that time can force lush, vegetative growth that will not have a chance to harden off before the onset of cold weather.
How-to : Fertilization for Annuals and Perennials
Annuals and perennials may be fertilized using: 1.water-soluble, quick release fertilizers; 2. temperature controlled slow-release fertilizers; or 3. organic fertilizers such as fish emulsion. Water soluble fertilizers are generally used every two weeks during the growing season or per label instructions. Controlled, slow-release fertilizers are worked into the soil ususally only once during the growing season or per label directions. For organic fertilizers such as fish emulsion, follow label directions as they may vary per product.
LightConditions : Partial Shade
Partial Shade is defined as filtered light found beneath trees with high limbs. Partial shade usually offers some protection from direct afternoon sun.
Conditions : Filtered Light
For many plants that prefer partially shady conditions, filtered light is ideal. Good planting sites are under a mid to large sized tree that lets some light through their branches or beneath taller plants that will provide some protection.
Conditions : Partial Sun, Partial Shade
Part sun or part shade plants prefer light that is filtered. Sunlight, though not direct, is important to them. Often morning sun, because it is not as strong as afternoon sun, can be considered part sun or part shade. If you live in an area that does not get much intense sun, such as the Pacific Northwest, a full sun exposure may be fine. In other areas such as Florida, plant in a location where afternoon shade will be received.
Conditions : Types of Pruning
Types of pruning include: pinching, thinning, shearing and rejuvenating.
Pinching is removing the stem tips of a young plant to promote branching. Doing this avoids the need for more severe pruning later on.
Thinning involves removing whole branches back to the trunk. This may be done to open up the interior of a plant to let more light in and to increase air circulation that can cut down on plant disease. The best way to begin thinning is to begin by removing dead or diseased wood.
Shearing is leveling the surface of a shrub using hand or electric shears. This is done to maintain the desired shape of a hedge or topiary.
Rejuvenating is removal of old branches or the overall reduction of the size of a shrub to restore its original form and size. It is recommended that you do not remove more than one third of a plant at a time. Remember to remove branches from the inside of the plant as well as the outside. When rejuvenating plants with canes, such as nandina, cut back canes at various heights so that plant will have a more natural look.
Conditions : Full Sun
Full Sun is defined as exposure to more than 6 hours of continuous, direct sun per day.
WateringConditions : Regular Moisture for Outdoor Plants
Water when normal rainfall does not provide the preferred 1 inch of moisture most plants prefer. Average water is needed during the growing season, but take care not to overwater. The first two years after a plant is installed, regular watering is important. The first year is critical. It is better to water once a week and water deeply, than to water frequently for a few minutes.
Conditions : Moist and Well Drained
Moist and well drained means exactly what it sounds like. Soil is moist without being soggy because the texture of the soil allows excess moisture to drain away. Most plants like about 1 inch of water per week. Amending your soil with compost will help improve texture and water holding or draining capacity. A 3 inch layer of mulch will help to maintain soil moisture and studies have shown that mulched plants grow faster than non-mulched plants.
Conditions : Outdoor Watering
Plants are almost completely made up of water so it is important to supply them with adequate water to maintain good plant health. Not enough water and roots will wither and the plant will wilt and die. Too much water applied too frequently deprives roots of oxygen leading to plant diseases such as root and stem rots. The type of plant, plant age, light level, soil type and container size all will impact when a plant needs to be watered. Follow these tips to ensure successful watering:
* The key to watering is water deeply and less frequently. When watering, water well, i.e. provide enough water to thoroughly saturate the root ball. With in-ground plants, this means thoroughly soaking the soil until water has penetrated to a depth of 6 to 7 inches (1' being better). With container grown plants, apply enough water to allow water to flow through the drainage holes.
* Try to water plants early in the day or later in the afternoon to conserve water and cut down on plant stress. Do water early enough so that water has had a chance to dry from plant leaves prior to night fall. This is paramount if you have had fungus problems.
* Don't wait to water until plants wilt. Although some plants will recover from this, all plants will die if they wilt too much (when they reach the permanent wilting point).
* Consider water conservation methods such as drip irrigation, mulching, and xeriscaping. Drip systems which slowly drip moisture directly on the root system can be purchased at your local home and garden center. Mulches can significantly cool the root zone and conserve moisture.
* Consider adding water-saving gels to the root zone which will hold a reserve of water for the plant. These can make a world of difference especially under stressful conditions. Be certain to follow label directions for their use.
Conditions : Normal Watering for Outdoor Plants
Normal watering means that soil should be kept evenly moist and watered regularly, as conditions require. Most plants like 1 inch of water a week during the growing season, but take care not to over water. The first two years after a plant is installed, regular watering is important for establishment. The first year is critical. It is better to water once a week and water deeply, than to water frequently for a few minutes.
PlantingHow-to : Preparing Garden Beds
Use a soil testing kit to determine the acidity or alkalinity of the soil before beginning any garden bed preparation. This will help you determine which plants are best suited for your site. Check soil drainage and correct drainage where standing water remains. Clear weeds and debris from planting areas and continue to remove weeds as soon as they come up.
A week to 10 days before planting, add 2 to 4 inches of aged manure or compost and work into the planting site to improve fertility and increase water retention and drainage. If soil composition is weak, a layer of topsoil should be considered as well. No matter if your soil is sand or clay, it can be improved by adding the same thing: organic matter. The more, the better; work deep into the soil. Prepare beds to an 18 inch deep for perennials. This will seem like a tremendous amount of work now, but will greatly pay off later. Besides, this is not something that is easily done later, once plants have been established.
How-to : Planting Bulbs
Plant bulbs at a depth that is three times their height, and at least 1-1/2 bulb-widths apart. Work a little bone meal fertilizer into the bottom of your hole, and then place the bulb upright in the hole. The more pointed end is almost always the top. If you have trouble telling which is the top, look for evidence of where a stem or roots were last year. If in doubt, plant them sideways. Fill in with soil gently, making sure there are no rocks or clods that would impede the bulb's stem. When planting a great number of bulbs, dig out an area to the specified depth, place bulbs and replace soil. This ensures that ground has been properly prepared and bulbs are evenly spaced.
Plant bulbs in natural drifts rather that formal rows: bulbs can fail or be eaten, leaving holes in a formal arrangement, or will shift with freezing and thawing. If you have trouble with gophers or squirrels eating your bulbs, try sprinkling red pepper in the holes, covering the bulbs with chicken-wire, surround bulbs with sharp shards of gravel or other substance, or planting rodent-repelling bulbs like Fritillaria nearby.
How-to : Pinching and Thinning Perennials
Once you plant a perennial, it does not mean that you will enjoy years of maintenance-free gardening. Perennials need to be cared for just like any other plant. One thing that distinguishes perennials is that they tend to be active growers that have to be thinned out occasionally or they will loose vigor.
As perennials establish, it is important to prune them back and thin them out occasionally. This will prevent them from completely taking over an area to the exclusion of other plants, and also will increase air circulation thereby reducing the incidence of diseases like botrytis and powdery mildew.
Many species also flower abundantly and produce ample seed. As blooms fade it is advisable to deadhead your plant; that is, to remove spent flowers before they form seed. This will prevent your plants from seeding all over the garden and will conserve the considerable energy it takes the plant to produce seed.
As perennials mature, they may form a dense root mass that eventually leads to a less vigorous plant. It is advisable to occasionally thin out a stand of such perennials. By dividing the root system, you can make new plants to plant in another area of the garden or give away. Also root pruning will stimulate new growth and rejuvenate the plant. Most perennials may be successfully divided in either spring or fall. Do a little homework; some perennials do have a preference.
How-to : Planting Perennials
Determine appropriate perennials for your garden by considering sun and shade through the day, exposure, water requirements, climate, soil makeup, seasonal color desired, and position of other garden plants and trees.
The best times to plant are spring and fall, when soil is workable and out of danger of frost. Fall plantings have the advantage that roots can develop and not have to compete with developing top growth as in the spring. Spring is more desirable for perennials that dislike wet conditions or for colder areas, allowing full establishment before first winter. Planting in summer or winter is not advisable for most plants, unless planting a more established sized plant.
To plant container-grown plants: Prepare planting holes with appropriate depth and space between. Water the plant thoroughly and let the excess water drain before carefully removing from the container. Carefully loosen the root ball and place the plant in the hole, working soil around the roots as you fill. If the plant is extremely root bound, separate roots with fingers. A few slits made with a pocket knife are okay, but should be kept to a minimum. Continue filling in soil and water thoroughly, protecting from direct sun until stable.
To plant bare-root plants: Plant as soon as possible after purchase. Prepare suitable planting holes, spread roots and work soil among roots as you fill in. Water well and protect from direct sun until stable.
To plant seedlings: A number of perennials produce self-sown seedlings that can be transplanted. You may also start your own seedling bed for transplanting. Prepare suitable planting holes, spacing appropriately for plant development. Gently lift the seedling and as much surrounding soil as possible with your garden trowel, and replant it immediately, firming soil with fingertips and water well. Shade from direct sun and water regularly until stable.
How-to : Plant Bulbs
It's time to plant bulbs.
ProblemsPest : Thrips
Thrips are small, winged insects that attack many types of plants and thrive in hot, dry conditions (like heated houses). They can multiply quickly as a female can lay up to 300 eggs in a life span of 45 days without mating. Most of the damage to plants is caused by the young larvae which feed on tender leaf and flower tissue. This leads to distorted growth, injured flower petals and premature flower drop. Thrips also can transmit many harmful plant viruses.
Prevention and Control: keep weeds down and use screening on windows to keep them out. Remove or discard infested plants, keep them away from non-infested plants. Trap with yellow sticky cards or take advantage of natural enemies such as predatory mites. Sometimes a good steady shower of water will wash them off the plant. Consult your local garden center professional or county Cooperative extension office for legal chemical recommendations.
Pest : Spider Mites
Spider mites are small, 8 legged, spider-like creatures which thrive in hot, dry conditions (like heated houses). Spider mites feed with piercing mouth parts, which cause plants to appear yellow and stippled. Leaf drop and plant death can occur with heavy infestations. Spider mites can multiply quickly, as a female can lay up to 200 eggs in a life span of 30 days. They also produce a web which can cover infested leaves and flowers.
Prevention and Control: Keep weeds down and remove infested plants. Dry air seems to worsen the problem, so make sure plants are regularly watered, especially those preferring high humidity such as tropicals, citrus, or tomatoes. Always check new plants prior to bringing them home from the garden center or nursery. Take advantage of natural enemies such as ladybug larvae. If a miticide is recommended by your local garden center professional or county Cooperative Extension office, read and follow all label directions. Concentrate your efforts on the undersides of the leaves as that is where spider mites generally live.
Pest : Fungus Gnats and Shoreflies
Fungus Gnats or Shore fliesare small pesky flies which can often be a nuisance inside the home. About the size of fruit flies, they can be seen running on the soil surface of pots. They seem to favor wet soil conditions and may thrive in mixes containing hardwood bark or manure. While the worm-like larvae can cause root damage and adults can transmit plant diseases, they rarely cause severe plant damage.
Possible controls: avoid over-watering soil. Another option: use labelled insecticidal drenches against the juvenile stages. Adults can be controlled with recommended insecticides, as well. Encourage natural enemies such as parasitic nematodes in the garden.
Diseases : Bulb Rot
Improperly stored bulbs, or bulbs that are too wet in their dormant stage (usually summer), will be susceptible to fungal diseases that cause them to rot. To prevent this, store bulbs properly when out of the ground. Avoid planting bulbs in poorly drained soils. Fusarium bulb rot can be a serious problem which attacks both the growing plant and stored bulb. Usually introduced by an infected bulb, corm, soil, or even tools, the fungus enters the plant through an abrasion in the tissue. This problem is worse in warm climates where temperatures rarely drop into the freezing range and can persist in soil that stays 60 to 70 degrees Farenheit. Prevention and Control: Buy bulbs that are firm, not mushy. Avoid planting new bulbs in areas where the disease has been present. Unfortunately, there is no treatment for Fusarium bulb rot. Remove all infected bulbs and soil in the immediate area.
Fungi : Rusts
Most rusts are host specific and overwinter on leaves, stems and spent flower debris. Rust often appears as small, bright orange, yellow, or brown pustules on the underside of leaves. If touched, it will leave a colored spot of spores on the finger. Caused by fungi and spread by splashing water or rain, rust is worse when weather is moist.
Prevention and Control: Plant resistant varieties and provide maximum air circulation. Clean up all debris, especially around plants that have had a problem. Do not water from overhead and water only during the day so that plants will have enough time to dry before night. Apply a fungicide labeled for rust on your plant.
Fungi : Leaf Spots
Leaf spots are caused by fungi or bacteria. Brown or black spots and patches may be either ragged or circular, with a water soaked or yellow-edged appearance. Insects, rain, dirty garden tools, or even people can help its spread.
Prevention and Control: Remove infected leaves when the plant is dry. Leaves that collect around the base of the plant should be raked up and disposed of. Avoid overhead irrigation if possible; water should be directed at soil level. For fungal leaf spots, use a recommended fungicide according to label directions.
MiscellaneousConditions : Deer Tolerant
There are no plants that are 100% deer resistant, but many that are deer tolerant. There are plants that deer prefer over others. You will find that what deer will or will not eat varies in different parts of the country. A lot of it has to do with how hungry they are. Most deer will sample everything at least once, decide if they like it or not and return if favorable. A fence is the good deer barrier. You may go for a really tall one (7 to 8 feet), or try 2 parallel fences, (4 to 5 feet apart). Use a wire mesh fence rather than board, since deer are capable of wiggling through a 12 inch space.
Conditions : Rabbit Tolerant
As cute as they are, rabbits can really damage a vegetable garden. Young, tender lettuce plants seem to be their favorite. If a free-roaming dog is not a possibility for you, consider installing raised vegetable beds and covering tender shoots with netting. If you have ample room, you can opt to plant enough for you and the bunnies. Scents don't always repel animals, as they get used to them and are often washed off in the rain.
How-to : Cut Flowers
Flowers suitable for cutting maintain their form for several days when properly conditioned and placed in water or soaked oasis. A cut flower should have a fairly strong, long stem, making it easy to work with in arrangements. There are many short stem flowers that make good cut flowers too, but they look best when floated in a bowl or clustered and placed in a juice glass size vase.
For best results, always cut flowers early in the morning, preferably before dew has had a chance to dry. Always make cuts with a sharp knife or pruners and plunge flowers or foliage into a bucket of water. Store in a cool place until you are ready to work with them, this will keep flowers from opening. Always re-cut stems and change water frequently. Washing vases or containers to rid of existing bacteria helps increase their life, as well.
How-to : Dried Flowers
Some cut flowers make excellent dried flowers. Good dried flower candidates hold their color, form, and often fragrance once dried. Large, fleshy-petaled flowers do not dry well. Air drying is the easiest. Make sure that flowers are not damp. Tie them in a small bunch and hang upside down in a dark, well-ventilated room. Silicone drying is another popular method and crystals can be bought in craft stores.
Edibles : Edible Flowers
Some flowers are edible or have edible portions that are not only beautiful, but nutritious and tasty. Buds, flowers, leaves, stems, and roots are selected from designated edible varieties. Plant as you would a regular flower, but use only organic practices. If you are not a total organic gardener, separate growing areas should be used for the growing of edible flowers.
When portions of edible flowers are desired, pull petals or edible portions from fresh flowers and snip off the petals from the base of the flower. Remember to always wash flowers thoroughly making certain any residue or dirt has been removed. Give them a gentle bath in water and then dip the petals in ice water to perk them up. Drain on paper towels. Petals and whole flowers may be stored for a short time in plastic bags in refrigeration. Freeze whole small flowers in ice rings or cubes. Make sure you know what the flower is before you eat it; have an accurate identification done.
Glossary : Border Plant
A border plant is one which looks especially nice when used next to other plants in a border. Borders are different from hedges in that they are not clipped. Borders are loose and billowy, often dotted with deciduous flowering shrubs. For best effect, mass smaller plants in groups of 3, 5, 7, or 9. Larger plants may stand alone, or if room permits, group several layers of plants for a dramatic impact. Borders are nice because they define property lines and can screen out bad views and offer seasonal color. Many gardeners use the border to add year round color and interest to the garden.
Glossary : Naturalizing
Naturalizing refers to planting in a random pattern, much as itwould occur in nature. If you spend any time in the woods, you've probably noticed that plants often grow in groups. The center of the group is dense and towards the edges, plants are located farther apart. Narcissus bulbs are easy to naturalize if you use this method: fill a bucket with bulbs and toss them out. Plant them where they fall. You will notice a portion of the bulbs are close together while the others have scattered farther away.
Glossary : Bulbs
A bulb is a modified, underground stem.
Glossary : Herbaceous
Herbaceous refers to a non-woody plant that dies back at the end of its growing season, generally after frost or during the fall of the year. The rootstock of perennials will overwinter, providing the plant is hardy in that area, and resume growth in the spring.
Glossary : Perennial
Perennial: traditionally a non-woody plant that lives for two or more growing seasons.
Glossary : Seed Start
Seed Start: easily propagated from seed.
Glossary : Fragrant
Fragrant: having fragrance.
Glossary : pH
pH, means the potential of Hydrogen, is the measure of alkalinity or acidity. In horticulture, pH refers to the pH of soil. The scale measures from 0, most acid, to 14, most alkaline. Seven is neutral. Most plants prefer a range between 5.5 and about 6.7, an acid range, but there are plenty of other plants that like soil more alkaline, or above 7. A pH of 7 is where the plant can most easily absorb the most nutrients in the soil. Some plants prefer more or less of certain nutrients, and therefore do better at a certain pH.
Glossary : Edibles
An edible is a plant that has a part or all of it that can be safely consumed in some way.
Glossary : Tolerant
Tolerant refers to a plant's ability to tolerate exposure to an external condition(s). It does not mean that the plant thrives or prefers this situation, but is able to adapt and continue its life cycle.
Glossary : Viruses
Viruses, which are smaller than bacteria, are not living and do not replicate on their own. They must rely on the cellular mechanisms of their hosts to replicate. Because this greatly disrupts the cell's functionality, outward signs of a viral infection result in a plant disease with symptoms such as abnormal or stunted growth, damaged fruit, discolorations or spots.
Prevention and Control: Keep virus carriers such as aphids, leafhoppers, and thrips under control. These plant feeding insects spread viruses. Viruses can also be introduced by infected pollen or through plant openings (as when pruning). Begin by keeping the pathogen out of your garden. New plants should be checked, as well as tools and existing plants. Use only certified seed that is deemed disease-free. Plant only resistant varieties and create a discouraging environment by rotating crops, not planting closely related plants in the same area every year.