‘Roi Humbert’ pairs purple leaves with gold flushes to brilliant red flowers. Bold-leaved perennial with flowers summer to frost. Casually shaped five-petal flowers to 5 inches wide held above the foliage on tall stems. Flowers may be red, yellow, orange, pink or salmon. Adds a tropical look to the landscape. Large (to 2 feet) leaves are green, sometimes marked with bronze stripes. Effective in mass plantings, or containers. Very easy to grow.
Google Plant Images: click here!
CharacteristicsCultivar: Roi Humbert
Size:Height: 1 ft. to 5 ft.
Width: 0.42 ft. to 1.67 ft.
Plant Characteristics:seed start, spreading,
Foliage Characteristics:coarse leaves,
Flower Characteristics:long lasting, unusual,
Tolerances:heat & humidity,
Bloomtime Range: Mid Summer to Mid Fall
USDA Hardiness Zone:8 to 11
AHS Heat Zone:Not defined for this plant
Light Range:Sun to Full Sun
pH Range:5 to 8
Soil Range:Mostly Sand to Some Clay
Water Range:Normal to Moist
FertilizingHow-to : Fertilize Monthly
Now is the time to begin fertilizing with a water-soluble fertilizer. Continue through the end of summer.
LightConditions : Light Conditions
Unless a site is completely exposed, light conditions will change during the day and even during the year. The northern and eastern sides of a house receive the least amount of light, with the northern exposure being the shadiest. The western and southern sides of a house receive the most light and are considered the hottest exposures due to intense afternoon sun.
You will notice that sun and shade patterns change during the day. The western side of a house may even be shady due to shadows cast by large trees or a structure from an adjacent property. If you have just bought a new home or just beginning to garden in your older home, take time to map sun and shade throughout the day. You will get a more accurate feel for your site's true light conditions.
Conditions : Full to Partial Sun
Full sunlight is needed for many plants to assume their full potential. Many of these plants will do fine with a little less sunlight, although they may not flower as heavily or their foliage as vibrant. Areas on the southern and western sides of buildings usually are the sunniest. The only exception is when houses or buildings are so close together, shadows are cast from neighboring properties. Full sun usually means 6 or more hours of direct unobstructed sunlight on a sunny day. Partial sun receives less than 6 hours of sun, but more than 3 hours. Plants able to take full sun in some climates may only be able to tolerate part sun in other climates. Know the culture of the plant before you buy and plant it!
Conditions : Light and Plant Selection
For best plant performance, it is desirable to match the correct plant with the available light conditions. Right plant, right place! Plants which do not receive sufficient light may become pale in color, have fewer leaves and a "leggy" stretched-out appearance. Also expect plants to grow slower and have fewer blooms when light is less than desirable. It is possible to provide supplemental lighting for indoor plants with lamps. Plants can also receive too much light. If a shade loving plant is exposed to direct sun, it may wilt and/or cause leaves to be sunburned or otherwise damaged.
WateringProblems : Waterlogged Soil and Solutions
Waterlogged soil occurs when more water is added to soil than can drain out in a reasonable amount of time. This can be a severe problem where water tables are high or soils are compacted. Lack of air space in waterlogged soil makes it almost impossible for soil to drain. Few plants, except for bog plants, can tolerate these conditions. Drainage must be improved if you are not satisfied with bog gardening. Over-watered plants have the same wilted leaves as under-watered plants. Fungi such as Phytophthora and Pythium affect vascular systems, which cause wilt.
If the problem is only on the surface, it maybe diverted to a drainage ditch. If drainage is poor where water table is high, install an underground drainage system. You should contact a contractor for this. If underground drains already exist, check to see if they are blocked.
French drains are another option. French drains are ditches that have been filled with gravel. It is okay to plant sod on top of them. More obtrusive, but a good solution where looks aren't as important, think of the French drain as a ditch filled with gravel. Ditches should be 3 to 4 feet deep and have sloping sides.
A soakway is a gravel filled pit where water is diverted to via underground pipes. This works well on sites that have compacted soil. Your soakway should be about 6'wide and deep and filled with gravel or crushed stone, topped with sand and sodded or seeded.
Keep in mind that it is illegal to divert water onto other people's property. If you do not feel that you can implement a workable solution on your own, call a contractor.
Tools : Watering Aides
No gardener depends 100% on natural rainfall. Even the most water conscious garden appreciates the proper hose, watering can or wand.
- Watering Cans: Whether you choose plastic of galvanized makes no difference, but do look for generous capacity and a design that is balanced when filled with water. A 2 gallon can (which holds 18 lbs. of water) is preferred by most gardeners and is best suited for outdoor use. Indoor cans should be relatively smaller with narrower spouts and roses (the filter head).
- Watering Hose: When purchasing a hose, look for one that is double-walled, as it will resist kinking. Quick coupler links are nice to have on ends of hoses to make altering length fast. To extend the life of your hose, keep it wound around a reel and stored in a shady area. Prior to winter freezes, drain hose.
- Sprayers: Are commonly thought of as devices for applying chemicals, but can really be a step saver for watering houseplants or small pots of annuals rather that dragging out a hose or making numerous trips with a watering can. The backpack sprayer is best suited for this. Take care not to use any kind of chemical in tanks used for watering!
- Sprinklers: Attached to the ends of garden hoses, these act as an economical irrigation system. Standing Spike Sprinklers are usually intended for lawns and deliver water in a circular pattern. Rotating Sprinklers deliver a circle of water and are perfect for lawns, shrubs and flower beds. Pulse-jet sprinklers cover large areas of ground in a pulsating, circular pattern. The head usually sits up on a tall stem, except for when watering lawns. Oscillating sprinklers are best for watering at ground level in a rectangular pattern.
Conditions : Water Conditions
When selecting Water Conditions, take into account the amount of water this particular area of your site receives naturally. If you have an irrigation system, select the default normal. Some sites may be naturally wet due to boggy areas by down spots or very dry due to a high sand content. By working with your site's natural conditions, you will reduce maintenance. Do note that even the most drought tolerant plant must first become established, so be willing to provide about 1 inch of water per week during the first year or two.
Conditions : Normal Watering for Houseplants
Houseplants that require normal watering should be watered so that soil is completely saturated and excess water runs out the bottom of the pot. Never water just a little bit; this allows mineral salts to build up in the soil. The key to normal watering is to allow the top inch or two of potting soil to dry out between waterings. Check frequently as certain times of the year may dictate that you water more frequently. Also, some plants that require normal watering during the growing season, may require less during the winter months when they are dormant.
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.
Conditions : Indoor Watering
Plant are composed of almost 90% water so it important to supply them with adequate water. Proper watering is essential for good plant health. When there is not enough water, roots will wither and the plant will wilt. When too much water is applied too frequently, roots are deprived of oxygen and diseases occur 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 frequency. Water well then wait long enough until the plant needs to be re-watered according to its moisture requirements.
* When watering, water well. That is, provide enough water to thoroughly saturate the root ball. With containerized plants, apply enough water to allow water to flow through the drainage holes.
* Avoid using cold water especially with houseplants. This can shock tender roots. Fill watering can with tepid water or allow cold water to sit for a while to come to room temperature before watering. This is a good way to allow any harmful chlorine in the water to evaporate before being used.
* Some plants are best irrigated by sub-irrigation, i.e. watering from the bottom up. This avoids splashing water on the leaves of sensitive plants. Simply place the pot in a shallow pan filled with tepid water and let the plant sit for 15 minutes to allow the root ball to be thoroughly wet. Take out and allow sufficient drainage.
* Use an unpainted dowel to help you determine when to re-water larger pots. Stick it into the soil ball & wait 5 minutes. The dowel will absorb moisture from the soil and turn a darker color. Pull it out and examine. This will give you an idea of how wet the soil root ball is.
* Roots need oxygen to breath, do not allow plants to sit in a saucer filled with water. This will only promote disease.
PlantingHow-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 : Potting Indoor Plants
Make sure that the plant you have chosen is suitable for the conditions you are able to provide it: that it will have enough light, space, and a temperature it will like. Remember that the area right next to a window will be colder than the rest of the room.
Indoor plants need to be transplanted into a larger container periodically, or they become pot/root-bound and their growth is retarded. Water the plant well before starting, so the soil will hold the root ball together when you remove it from the pot. If you have trouble getting the plant out of the pot, try running a blade around the edge of the pot, and gently whacking the sides to loosen the soil.
Always use fresh soil when transplanting your indoor plant. Fill around the plant gently with soil, being careful not to pack too tightly -- you want air to be able to get to the roots. After the plant is in the new pot, don't fertilize right away... this will encourage the roots to fill in their new home.
The size pot you choose is important too. Select one that is not more than about 1 inch greater in diameter. Remember, many plants prefer being somewhat pot bound. Always start with a clean pot!
How-to : Sow Seed
Now is the preferred time to sow seed.
ProblemsPest : 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 : Slugs and Snails
Slugs and snails favor moist climates and are mollusks, not insects. They can be voracious feeders, eating just about anything that is not woody or highly scented. They may eat holes in leaves, strip entire stems, or completely devour seedlings and tender transplants, leaving behind tell-tale silvery, slimy trails.
Prevention and control: Keep your garden as clean as possible, eliminating hiding places such as leaf debris, over-turned pots, and tarps. Groundcover in shady places and heavy mulches provide protection from the elements and can be favorite hiding places. In the spring, patrol for and destroy eggs (clusters of small translucent spheres) and adults during dusk and dawn. Set out beer traps from late spring through fall.
Many chemical controls are available on the market, but can be poisonous and deadly for children and pets; take care when using them - always read the label first!
Pest : Caterpillars
Caterpillars are the immature form of moths and butterflies. They are voracious feeders attacking a wide variety of plants. They can be highly destructive and are characterized as leaf feeders, stem borers, leaf rollers, cutworms and tent-formers.
Prevention and Control: keep weeds down, scout individual plants and remove caterpillars, apply labeled insecticides such as soaps and oils, take advantage of natural enemies such as parasitic wasps in the garden and use Bacillus thuringiensis (biological warfare) for some caterpillar species.
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.
MiscellaneousGlossary : Container Plant
A plant that is considered to be a good container plant is one that does not have a tap root, but rather a more confined, fibrous root system. Plants that usually thrive in containers are slow- growing or relatively small in size. Plants are more adaptable than people give them credit for. Even large growing plants can be used in containers when they are very young, transplanted to the ground when older. Many woody ornamentals make wonderful container plants as well as annuals, perennials, vegetables, herbs, and bulbs.
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.
Conditions : Site Conditions
When setting criteria for site conditions, check boxes that apply to your planting area. This will narrow the search for appropriate plants. Naturally, you'll need to select a USDA Hardiness Zone. Selecting a specific soil type and pH are just as important as light and water conditions because they enable a search that will find plants best suited to your site.
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 : Plant Characteristics
Plant characteristics define the plant, enabling a search that finds specific types of plants such as bulbs, trees, shrubs, grass, perennials, etc.
Glossary : Flower Characteristics
Flower characteristics can vary greatly and may help you decide on a ""look or feel"" for your garden. If you're looking for fragrance or large, showy flowers, click these boxes and possibilities that fit your cultural conditions will be shown. If you have no preference, leave boxes unchecked to return a greater number of possibilities.
Glossary : Foliage Characteristics
By searching foliage characteristics, you will have the opportunity to look for foliage with distinguishable features such as variegated leaves, aromatic foliage, or unusual texture, color or shape. This field will be most helpful to you if you are looking for accent plants. If you have no preference, leave this field blank to return a larger selection of plants.
Glossary : Soil Types
A soil type is defined by granule size, drainage, and amount of organic material in the soil. The three main soil types are sand, loam and clay. Sand has the largest particle size, no organic matter, little to no fertility, and drains rapidly. Clay, at the opposite end of the spectrum, has the smallest particle size, can be rich in organic matter, fertility and moisture, but is often unworkable because particles are held together too tightly, resulting in poor drainage when wet, or is brick-like when dry. The optimum soil type is loam, which is the happy median between sand and clay: It is high in organic matter, nutrient-rich, and has the perfect water holding capacity.
You will often hear loam referred to as a sandy loam (having more sand, yet still plenty of organic matter) or a clay loam (heavier on the clay, yet workable with good drainage.) The addition of organic matter to either sand or clay will result in a loamy soil. Still not sure if your soil is a sand, clay, or loam? Try this simple test. Squeeze a handfull of slightly moist, not wet, soil in your hand. If it forms a tight ball and does not fall apart when gently tapped with a finger, your soil is more than likely clay. If soil does not form a ball or crumbles before it is tapped, it is sand to very sandy loam. If soil forms a ball, then crumbles readily when lightly tapped, it's a loam. Several quick, light taps could mean a clay loam.
How-to : Getting the Most Out of Cut Flowers
Cut flowers bring the garden into your home. While some cut flowers have a long vase life, most are highly perishable. How cut flowers are treated when you first bring them home can significantly increase how long they last.
The most important thing to consider is getting sufficient water taken up into the cut stem. Insufficient water can result in wilting and short-lived flowers. Bent neck of roses, where the flower head droops, is the result of poor water uptake. To maximize water uptake, first re-cut the stems at an angle so that the vascular system (the ""plumbing"" of the stem) is clear. Next immerse the cut stems in warm water.
Remember when the flower is cut, it is cut off from its food supply. Once water is taken care of, food is the resource that will run out next. The plants stems naturally feed the flowers with sugars. If you add a bit of sugar (1 tsp.) to the vase water, this will help feed the flower stems and extend their vase life.
Bacteria will build up in vase water and eventually clog up the stem so the flower cannot take up water. To prevent this, change the vase water frequently and make a new cut in the stems every few days.
Floral preservatives, available from florists, contain sugars, acids and bacteriacides that can extend cut flower life. These come in small packets and are generally available where cut flowers are sold. If used properly, these can extend the vase life of some cut flowers 2 to 3 times when compared with just plain water in the vase.
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 : Fertilize
Fertilize just before new growth begins with a complete fertilizer.