Flowering Hanging Baskets

Commercial Greenhouse Production



Dr. J. Raymond Kessler, Jr.

Auburn University



Introduction

The production of flowering hanging baskets during the annual bedding plant season has become an important part of greenhouse production. Hanging baskets allow growers to utilize areas over benches, aisles and pathways to generate significant revenues and take advantage of areas which must be heated and covered in glazing anyway. However, utilization of overhead areas do not preclude the development of production areas dedicated to basket production. In fact, many businesses have developed whole greenhouses or sections that use various staggered basket hanging schemes. In either case, careful planning of the production facility and crop scheduling is required. The temptation is to over produce in a given area or shrink production times to get as much production as possible during the spring market window. Development and adherence to production schedules and product standards are mandatory to maintaining product quality and uniformity.

The number and kinds of plants produced in hanging baskets varies with the development of new cultivars by breeders, introduction of species, and demands the marketplace. The most commonly grown plants are shown in the table.

Flowering hanging basket crop and common propagation methods.
Crop Propagation Method
Wax Begonia Seed
Fuchsia Cutting
Impatiens Seed
New Guinea Im. Cutting
Ivy Geranium Cutting
Lantana Cutting

The decision to propagate plant materials in house or purchase rooted cuttings or plug grown seedlings must be made based on time, labor, facilities and bench space. If the grower currently produces plugs for a bedding program, then seedling production for hanging baskets can be incorporated into that program. However, growers who are not currently set up for plug production should probably order plugs from specialists propagators. It is usually preferable to order rooted cutting from specialists propagators to be assured of disease and virus free material. However, when scheduled carefully, early shipments and plantings can serve as a source of cuttings for later plants. Removing cuttings also serves as a pinch to the orginal basket.

Containers and planting

The most commonly used hanging basket containers are 8, 10 and 12 inch plastic pots with snap-on plastic or wire hangers. Many designs are available, even those with planting holes on the side of the pot. In selecting a hanging basket, make sure the hangers can be quickly and easily attached to the pots and that the hangers are strong enough to support the weight of the pot, wet media and plant without breaking. Saucers should also snap in place easily and quickly but remain in place.

The growing medium must be a well-drained, well-aerated mix suited to the species being grown. Most reputable commercial mixes or grower-made mixes with these properties and proper pH and fertility adjustments work well.

The number of seedlings or cuttings (starters) planted per pot depends on starter plant quality and cost, species growth rate, pot size, and production time allotted. The number of starter plants per pot varies from 1 to 5 in an 8" basket with three being common, to 3 to 8 in a 10" pot with 4 or 5 being common. Fewer starters may be used when starter plant cost is high (i.e., usually those purchased from specialists propagators), bench space is available (i.e., early in the season), or the plant species grows fast and is naturally self-branching. However, the production time may be longer and labor costs higher if regular pinches are require to develop a full basket. More starters may be used when the species is slow growing, the labor costs or time required for pinching is high compared to the costs of starter plants (i.e., usually grower-produced starters), or the production time is limited (i.e., later in the season). Careful scheduling is required to balance these factors to obtain uniform quality for each crop during the season.

The planting depth for the starters should be shallow or at least no greater than the original depth of the propagating medium. Most growers arrange the starters in a ring around the outside of the pot with one or more toward the center (see figure). These arrangements allow the plants adequate growing room and to develop a uniform basket.

Some growers will hang the baskets in their final location immediately after potting. In this case, it is desirable to thoroughly water (a broad-spectrum fungicide may be included) the pots before hanging. Other growers will place newly planted baskets on benches, pot-to-pot, for a period of 2-6 weeks and then hang them in the final locations. During the bench time, starters can get established under the watchful eye of the grower and manual pinching can be accomplished easily. Which of the two methods to use depends on the cultural requirements for a species and space utilization.

Irrigation/Fertilization

Manual irrigation is infrequently used for hanging baskets except where an unplanned or one time crop may be grown for special purposes or holidays in an unequipped production area. Production areas designed for baskets frequently utilize automated timing systems and some form of drip emitters. The slow delivery of low volume emitters allows adequate lateral spread of water or fertilizer to saturate the large soil volume of these large containers and, with adequate control, addresses concerns regarding water conservation and ground water contamination. In fact, application rates which result in excessive dripping on bench crops below are undesirable and may result in diseases which require free water to spread such as Botrytis. Automated systems should be designed to deliver an equal amount of water to all pots on a watering station, then each station should be timed carefully to prevent dripping. Various programmable timing devices are available to set the required timing for each station and then cycle through the stations in a section or house. Automated Station cycling also places less demand on labor and water system pressure, in fact, with an additional 24 hour clock, the system may be activated to run early in the morning before employees arrive for work. Additional tips:

-- Design the emitter plumbing carefully. The most common problems are drip lines that are too long or have too many emitters to deliver water uniformly.

-- Evaluate water quality and incorporate in-line water filters if needed.

-- Before hanging a new crop, turn on the system and check for stopped up or slow emitters and leaking pipes. Clean the emitters if needed.

-- When hanging the pots, make sure each pot is receiving water from an emitter.

-- Check the pots periodically during the crop to make sure each pot is receiving water from an emitter.

Hanging baskets can be grown on the same fertilization schedule as bench and bedding plant crops. In a soilless media, 200-250 ppm nitrogen from a balanced fertilizer is sufficient. Weekly, leaching with clear water should be used to avoid high soluble salts problems.

Temperature

Each species in hanging baskets should be placed in a greenhouse or section which maintains temperatures compatible with that species. Plants such as petunia and ivy geranium require temperatures on the cool side while lantana and wax begonia prefer temperatures on the warm side. Keep in mind that temperatures higher up in the greenhouse may be warmer than at bench level.

Light

Each species in hanging baskets should be placed in a greenhouse or section with light levels compatible with that species. In addition, the light requirements of crops grown on benches or the floor below should be considered. In areas where baskets are tiered and staggered on multiple levels, hang the lower light requiring species toward the bottom and the higher light requiring species toward the top.

Pinching

One or more soft pinches are often applied to control overall size and shape of the hanging basket. Pinching forces plants to branch, and at the same time delays flowering. Therefore, the timing of pinches should be included into schedules. Pinching too early after planting will delay establishment, and pinching too late will result in poor branching form the hard woody stem below. The first pinch should be made when the root system has reached the side or bottom of the pot and active shoot growth is present. This usually occurs within the first 2-4 weeks after planting. A soft pinch should remove about the terminal " including the shoot apex, internodes below and possibly one expanding leaf. Subsequent pinches can be made at 3-6 week intervals depending on plant species, geographic location and growing conditions. Additional pinches result in fuller growth and add to quality but also adds significantly to total crop time. Experience, selling price and labor costs for the additional pinches must be considered in deciding on how many pinches to apply.

Many growers have experimented with Florel as a chemical pinching agent. Florel aborts flower buds and stops growth or aborts of the shoot apex thus releasing lateral shoots below to grow. Florel is not registered as a chemical pinching agent and the timing and concentration is crucial.

Scheduling

Accurate scheduling and keeping detailed records of previous crops is important to meet shipping dates. The grower must develop standard cultural practices for each hanging basket species for a given geographic location and time of year so that schedules can be workable and adhered to. Those in charge of acquisition of starters, baskets, media, etc. must work with suppliers to see that these materials arrive on time. Management must make sure that each production step is accomplished according to schedule.

Fuchsia

Fuchsias require long day plants for floral initiation. To flower early in the season, provide night interrupted lighting beginning 10 weeks before desired finishing date and light for 6 weeks. Provide good air circulation to keep humidity low and do not add the saucers until after shipping time to improve drainage. Drench with a broad-spectrum fungicide at planting.

Planting: Late fall to end of January, 3-5 plants per 10" basket.

Pinch: Pinch regularly and often. Allow new growth to develop, the pinch leaving two leaf nodes per stem. Last pinch no later than March 10 to flower for Mother's day.

Light: Full sun until no later than first or second week in April.

Temperature: Bench time 3-4 weeks at 62-65F night. Hung up at 60-64F night and 75F day.

Fertilizer: Fuchsias are heavy feeders.

Insects: Aphids, Whitefly, Thrips.

Diseases: Pythium, Phytopthora, Rhizotonia.

New Guinea Impatiens

Provide good air circulation to keep humidity low and do not add the saucers until after shipping time to improve drainage. Drench with a broad-spectrum fungicide at planting.

Planting: January to March, 3-4 plants per 10" basket.

Pinch: One soft pinch for the early plant dates (Jan - Feb). Generally not necessary thereafter.

Light: Full sun early, partial sun mid, bright shade late in the season.

Temperature: Bench time 3-4 weeks at 65-67F night. Hung up at 62-64F night and 70-75F day.

Fertilizer: New Guinea Impatiens are heavy feeders. Feed constantly but watch for soluble salts buildup.

Insects: Mites, Thrips.

Diseases: Pythium, Phytopthora, Rhizotonia, Botrytis.

Ivy Geranium

The most common problem is oedema, caused by excessive moisture on the leaves and in the soil. Water early in the morning and do not add the saucers until after shipping time to improve drainage. Keep growing temperatures on the low side. May need to add iron or calcium.

Planting: Late fall to February, 3-4 plants per 10" basket.

Pinch: New growth should be 1-1" for pinch or application of growth regulator. Cycocel or Florel promotes branching and early flowering. Apply growth regulator 10 weeks before desired finish.

Light: Full sun until no later than first or second week in April.

Temperature: Bench time 4-5 weeks at 60-62F night. Hung up at 58-60F night for stocky growth.

Fertilizer: Ivy geraniums are moderate feeders. Apply iron 1-2 times.

Insects: Thrips, Fungus gnats, Whitefly, Aphids.

Diseases: Pythium, Phytopthora, Botrytis.

Begonia

This group includes the Wax, Rieger, and Non-stop begonias. Provide good air circulation to keep humidity low. Add saucers at finishing time. Drench with broad-spectrum fungicide at planting time.

Planting: January to March, 3-5 plants per 10" basket.

Pinch: Pinch regularly and often. Allow nuw growth to develop, the pinch leaving two leaf nodes per stem. Last pinch no later than March 10 to flower for Mother's day.

Light: Full sun until first of April. Reiger and Non-stops need night interrupted lighting until March 15.

Temperature: Bench time 3-4 weeks at 65F minimum night. Hung up at 62F minimum night temperature.

Fertilizer: Begonias are light feeders. Use clear water often.

Insects: Thrips, cyclamen mites.

Diseases: Pythium, Phytopthora, Mildew.

Impatiens

Provide good air circulation to keep humidity low and do not add the saucers until after shipping time to improve drainage. Apply a broad-spectrum fungicide at planting

Planting: January to March, 3-4 plants per 10" basket.

Pinch: Apply several pinches with the last pinch no later than March 10.

Light: Full sun until no later than first or second week in April.

Temperature: Bench time 4 weeks at 64-65F night. Hung up at 62-64F night and 75F day.

Fertilizer: Impatiens are moderate feeders. Used clear water occasionally.

Insects: Whitefly, Thrips.

Diseases: Pythium, Phytopthora, Rhizotonia

Lantana

Provide good air circulation to keep humidity low and do not add the saucers until after shipping time to improve drainage. Apply a broad-spectrum fungicide at planting

Planting: January to March, 3-4 plants per 10" basket.

Pinch: Apply several pinches with the last pinch no later than March 10.

Light: Full sun until no later than first or second week in April.

Temperature: Bench time 4 weeks at 64-65F night. Hung up at 62-64F night and 75F day.

Fertilizer: Lantana is a moderate feeders.

Insects: Whitefly, Aphid.

Diseases: Mildew

Verbena

Provide good air circulation to keep humidity low and do not add the saucers until after shipping time to improve drainage. Apply a broad-spectrum fungicide at planting

Planting: January to March, 3-4 plants per 10" basket.

Pinch: Apply several pinches with the last pinch no later than March 10.

Light: Full sun until no later than first or second week in April.

Temperature: Bench time 4 weeks at 64-65F night. Hung up at 62-64F night and 75F day.

Fertilizer: Verbenas are moderate feeders.

Insects: Whitefly, Thrips.

Diseases: Mildew.