ANNUAL FLOWERS Debbie Lonnee, Mervin C. Eisel and Anne Hanchek

ANNUAL FLOWERS Debbie Lonnee, Mervin C. Eisel and Anne Hanchek By definition an annual plant completes its growth cycle in one growing season. The seed germinates and the plant produces leaves, produces flowers, produces seed and dies all in one growing season. Some plants commonly referred to as "annuals" are actually shortlived perennials in milder areas. These include snapdragons, dusty miller, pansies and others. Occasionally they will survive the winter in Minnesota, but are often weak and should be grown as annuals in Minnesota. Annuals have many uses and benefits as garden and patio plants as described in Tables 1 through 5. Many annuals have a long season of bloom, especially if old flowers are removed so they do not produce seed. Almost any color, including tints and shades, are available if different varieties of flowers are selected. Annuals are useful in providing color throughout the growing season. Some annuals can add fragrance to the garden and some are useful as cut flowers. There are some gardeners that like to segregate annuals and perennials in separate plantings, but many of the finest gardens combine annuals and perennials. Some annuals such as ageratum, sweet alyssum, and verbena, are useful as edging plants. Annuals can be used to fill voids where perennials have not survived the winter. Annuals have some disadvantages as a considerable amount of labor is required when growing annuals. This includes soil preparation, transplanting, and removing spent flowers, which can be time consuming or expensive if large areas are planted with annuals. Some annuals require a long period of time from a seedling to the flowering stage. If these annuals were seeded directly into the garden, it would be mid to late summer before they would start blooming. For this reason, in areas with a short growing season like Minnesota, a longer blooming period is achieved by germinating and starting seedlings indoors or in greenhouses. Some should be started as early as January while others should be started about six weeks prior to being transplanted into the garden. The ideal seedling size for transplanting is a small compact plant that is in bud, but not in bloom. Commercially, seedlings are often treated with a growth regulator to keep them compact. There are numerous trade publications, including many seed catalogs that provide this information as well as many other cultural techniques including germination temperatures, days to germination, and special requirements such as seed treatment, light, and more. Seedlings can be started in soilless mixes or pasteurized soil. Most seed should be covered with soil or growing medium to a depth of about twice the diameter of the seed. Some seeds such as impatiens require light to germinate so they should not be covered. Other seeds such as begonias are so small they cannot be covered or they will be planted too deeply. Begonia seed is often just pressed into the soil surface. For irrigation, seed trays or flats should be sub-irrigated to allow water to move upward by capillary action rather than overhead sprinkling which disturbs the seed. Many seeds will germinate at temperatures between 65º F and 75 o F, but commercial growers should consult references to check specific requirements for each crop. Light quality and intensity are important in producing quality annual seedlings. Although few plants require light to germinate, all require light once germination begins. Ample natural light is best, but seedlings can be started under artificial light. Attention to light quality is essential as the different kinds of florescent tubes emit different qualities of light. The cool end of the spectrum which is green and blue light is essential for vegetative growth. The red end of the spectrum is responsible for flowering. Cool white tubes should be used to grow seedlings prior to flowering. These are much less expensive and emit much more light than special plant tubes. Light intensity is also critical. Seedlings should be placed six to twelve inches from the lights. There is much less light emitted at the ends of the tubes. Once tube ends show signs of darkening they should be discarded as light intensity is further 14-1 1106

reduced. Many annuals are long day plants so they should be given 16-18 hours of light per day to achieve maximum growth. When seeds germinate, the first leaves are known as cotyledons. The subsequent leaves produced are the true leaves. Seedlings should be transplanted at the second pair of true leaves stage. Modern, commercial, annual operations use mechanical transplanters that carefully and automatically space the transplants. Annuals growing in hanging baskets or containers deplete water and nutrients more quickly than plants planted in the landscape. They must be watered daily and a water-soluble fertilizer applied weekly if a slow release fertilizer has not been incorporated into the media. Table 1. Annuals For Special Uses. Prior to transplanting the seedlings, they should be "hardened off" to reduce transplant shock. This includes increasing the amount of light, exposing the seedlings to outdoor air, lowering the temperature, and reducing water and fertilizer. This should be done seven to ten days prior to transplanting. A. Annuals for edging. Ageratum Begonia Dwarf Impatiens Pinks Sweet Alyssum Annual Phlox Dwarf Marigold Nierembergia Portulaca Verbena Beds devoted entirely to annuals should be tilled and fertilized prior to transplanting. Fertilizer should be based on needs determined by a soil test. If areas are small and testing is not practical, 1.5 to two pounds of 10-10-10 or a slow release 18-18-8 fertilizer per 100 square feet can be tilled into the soil before transplanting. It is better to use a slow release fertilizer where two to four pounds can be incorporated into the soil to last the growing season. Care should be taken to minimize root damage during transplanting and final planting. However, if the root ball is a solid mass of roots, it must be opened up, cut or pinched to prevent further root girdling. B. Annuals for cut flowers. Ageratum Annual Statice Aster Bachelor Buttons Bells of Ireland Blue Salvia Calendula Celosia Cleome Coleus Cosmos Heliotrope Impatiens Love-in-a-Mist Lisianthus Pansy Marigold Snapdragon Statice Zinnia Disease and insect control requirements for annuals are similar to requirements for other types of flowers. Some diseases can destroy plants if not properly managed. For example, marigolds can be killed by aster yellows, a virus-like disease that is spread by leafhoppers. Infested plants should be removed to prevent the disease from being spread. If seed does not come pretreated, it is desirable to treat seed with a fungicide prior to planting to prevent damping off. Damping off is a term used to describe diseases caused by Pythium, Rhizoctonia, and others, which rot the stem of the seedlings prior to emerging from the soil or just after emergence. Culturally adverse conditions including over watering, heavy shade, high fertility, high ph, poor air circulation, and contaminated media can contribute to this problem. Once damping off occurs, a fungicide can help control it, but withholding water, increasing light and air circulation will often favor the plant rather than the disease. 14-2 1106

Table 2. Annuals for shade gardens. Begonia 'Angel Wing' 12-48" 12-36" Upright Red, White, Pink Solid, Spotted, Edged Heat Tolerant Prominent Veination Begonia, Tuberous 8-15" 8-12" Upright, Mounding, Trailing Red, Pink, White, Coral, Yellow, Orange, Bicolor Begonia, Wax 6-10" 6-12" Mounding Red, White, Pink Browallia 10-15" 8-10" Upright White, Purple, Blue Bush Balsam 12-18" 3-9" Upright Red, White, Pink Caladium 10-20" 8-15" Upright White, Rose, Pink, Red,, Varigated Chicken Gizzard, Beefsteak Plant, Iresine 8-10" 12-36" Upright, Trailing Red, Pink, White Patterned Variegation Coleus, Seed 10-36" 6-18" Upright, Mounding White, Purple Red, Maroon, Brown, Pink, Yellow, Orange, White, Chartreuse Fuchsia 10-36" 8-24" Upright, Trailing Red, White, Pink, Purple, Bicolor Impatiens, Exotic, Seashell Impatiens Impatiens 8-24" most 8-10" 8-10" 6-10" Upright Orange, Yelllow, Coral 8-24" most 8-10" Upright, Mounding Red, Orange, Yellow, White, Pink, Purple, Coral, Bicolor Impatiens, New Guinea 8-14" 12-15" Upright, Trailing Red, Orange, Yellow, White, Pink, Purple, Coral, Bicolor Ivy, Hedera helix 12"-5' 9" Trailing (Juvenile Stage Only) Bright variegation, Deep Bronze White, White and Variegation Mimulus, Monkey 8-12" 6-9" Upright Red, Orange, Yellow, Flower White, Pink Perilla 10-36" 6-18" Upright White, Purple, Red, Burgundy Rose or Pink Centers Edged with Burgundy More Heat Tolerant than Coleus 14-3 1106

Table 2 (Continued). Annuals for shade gardens. Polka Dot Plant, 8-24" 12" Upright White, Pink, Red, Hypoestes Rose, Polka Dots, Patterns Spike Dracaena 18-24" 12-15" Upright Heat Tolerant Swedish Ivy, Plectranthus australis Torena, Wishbone Flower, Bluewings 12"-5' 9" Trailing White Fragrant Leaves 8-12" 6-18" Upright, Trailing White, Pink, Purple, Blue, Yellow, Bicolor, Tricolor Vinca minor 12"-5' 9" Upright, Trailing Blue, White, Bicolor Viola, Johnny Jump-ups 4-9" 6" Trailing Red, Orange, Yellow, White, Pink, Purple, Blue, Bicolor 14-4 1106

Table 3. Flowering plants for container gardens. Common Name Sun Sun Shade Height Width Habit Flower Color Agertum 5-8" 6-9" Mounding White, Pink, Purple, Blue White, Pink, Purple Alyssum, Sweet 3-8" 6-8" Mounding, Spreading Angelonia 8-20" 9-12" Upright White, Pink, Purple, Bicolor Bacopa 1-4" 6-9" Trailing White, Pink, Blue, Red Begonia, Wax 6-10" 6-12" Mounding Red, White, Pink Begonia, Rieger 10-14" 10-14" Mounding Red, Yelllow, White, Pink Begonia, Tuberous 8-15" 8-12" Trailing, Mounding Red, Yellow, White, Pink, Orange, Coral, Bicolor Begonia, Rex 6-12" 6-12" Mounding Red, White, Pink, Coral, Bicolor Bidens 10-12" 24-36" Spreading Yelllow Black-eyed Susan, Thunbergia 2-3' 12" Trailing, Vining Orange, White, Yellow Brachyscome 9-16" 6-12" Trailing Purple, White Browallia 10-15" 8-10" Upright Purple, White, Blue Bougainvillea 10-20' 5' Vining White, Pink, Purple, Orange, Gold Chenille Plant 6-20" 7-8" Vining, Drooping Red Coleus, Vegetative 10-36" 6-18" Upright, Mounding Purple, White Coleus, Seed 10-36" 6-18" Upright, Mounding Purple, White Cuphea, Mexican 6-9" 6-9" Upright Purple, Pink, Blue, White Heather Dahlia 6-15" 8-10" Mounding Red, Yellow, White, Pink, Orange, Purple, Bicolor Daisy, Marguerite 6-18" 9-15" Upright Yellow, White, Pink Diascia 6-12" 8" Spreading Red, White, Pink, Coral Dipladenia 3' 1' Vining Pink Dusty Miller 8-12" 8-10" Mounding Blue Evolvulus 8-12" 6-8" Mounding, Spreading Fuchsia 10-36" 8-24" Upright, Trailing Red, White, Pink, Purple, Bicolor Geranium, Ivy 6-12" 6-18" Trailing Red, White, Pink, Purple, Coral, Bicolor Geranium, Zonal 10-18" 8-12" Upright, Mounding Red, White, Pink, Purple, Coral, Bicolor Geranium, Seed 10-15" 8-12" Upright, Mounding Red, Orange, White, Pink, Purple, Coral, Bicolor Heliotrope 12-14" 12" Mounding Purple, White 14-5 1106

Table 3 (Continued). Flowering plants for container gardens. Common Name Sun Sun Shade Height Width Habit Flower Color Impatiens 8-24" 12-24" Mounding Red, Orange, Yellow, White, Pink, Purple, Coral, Bicolor Impatiens, Double 8-12" 8-12" Mounding Red, White, Pink, Purple, Coral, Bicolor Impatiens, New Guinea 8-14" 12-15" Mounding Red, Orange, Yellow, White, Pink, Purple, Coral, Bicolor Lantana 12-18" 8-12" Spreading Red, Orange, Yellow, White Lobelia 4-12" 4-12" Vining White, Purple, Blue Mandevila Vine 6' Trailing Pink, Yellow, White Million Bells/Mini 2' Spreading, Trailing Red, Yellolw, White, Pink, Purple Petunias, Calibrachoa Moss Rose 4-8" 10" Spreading Red, Orange, Yellow, White, Pink Nemesia 8-15" 10-12" Creeping Lavender, White, Blue, Pink Nolana 10" 15" Spreading Purple, Blue Nierembergia 3-6" 12" Spreading Purple, White Osteospermum 1-2' 12" Spreading Orange, Yellow, White, Purple Pansy 6-8" 6-12" Mounding Red, Orange, Yellow, Pink, Purple, White, Bicolor Pentas 12-22" 10-14" Upright Red, White, Pink, Lavender Petunias, Double 10-15" 12" Upright Burgundy, Orchid, Pink, Red, Rose, Salmon, White Petunia, Floribunda, 10-15" 12" Upright Burgundy, Lilac, Orchid, Pink, Rose, Red, Salmon, White, Yellow Multiflora Petunia, Grandiflora 10-15" 12" Upright Petunia, Hedgiflora 16-22" 12-15" Upright Cherry, Pink, Silver Petunia, Trailing 3-6" 36-48" Spreading, Trailing Blue, Lilac, Pink, Purple, Red, Rose, White Petunia, Trailing Double 3-12" 18-48" Mounding, Spreading Sanvitalia, Creeping Zinnia 8" 15" Prostrate, Spreading Lilac, Burgundy, Violet, Pink, Red, Blue, Salmon, White, Bicolor, some Stars Blue, Lavender, Lilac, Pink, Purple, White Scaevola, Fan Flower 10-14" 18-24" Mounding, Trailing Purple, White Snapdragon, Trailing 6-8" 12-24" Trailing Bronze, Yellow, Purple, Pink, White, Yellow Strawflower 12-36" 8-24" Upright Yellow, Pink, Red, White Torenia 8-12" 6-18" Upright, Trailing Blue, Purple, Pink, Yellow, White, Bicolor Verbena 6-10" 12-18" Trailing, Upright Red, White, Pink, Purple, Blue, Salmon, Bicolor Gold 14-6 1106

Table 4. Accent plants for container gardens. Common Name Sun Sun Shade Height Width Habit Flower Color Acorus 'Ogon' 12" 12" Upright Artemisia 'Oriental 24-36" 24-36" Upright Limelight' Asparagus Fern, 10-12" 12" Mounding Sprengeri Fern Candlestick Vine, 3' 18-24" Trailing Iboza Frosty Lace Mint 18-26" 12-24" Trailing Licorice Plant, 5' 5' Spreading Helichrysum Hedera helix, English Ivy 12"-5' 9" Trailing White Hibiscus 'Red Shield' 5' 5' Upright Lamium 4-6" 3' Trailing Lysimachia, 4-8" 3-4' Trailing Moneywort New Zealand Flax, Phormium 12"-4' 8-15" Upright Oregano, Golden 6" 6-18" Spreading, Trailing White Oregano 'Kent's Beauty' 6-12" 12-15" Mounding, Vase Purplish-Pink Bracts Shaped Pennisetum setaceum 'Rubrum' Pennisetum setaceum 'Burgundy Giant' Persian Shield, Strobilanthes 3-5' 2-4' Upright Pinkish Purple 3-6' 2-5' Upright Pinkish Purple 2-3' 18-24" Upright Plectranthus 1-3' 6-24" Upright Potato Vine, Ipomoea 2' 2' Trailing 'Aurea' Purple Spiderwort, Purple Heart 8-10" 8-10" Upright 14-7 1106

Table 4 (Continued). Accent plants for container gardens. Common Name Sun Sun Shade Height Width Habit Flower Color Sage, Berggarten 18-24" 12-20" Mounding Sage, Tricolor 18-24" 12-20" Mounding Blue Sage, Golden 12-15" 12-15" Mounding Spike Dracaena 18-24" 12-15" Upright Sweet Potato Vine, 3-10' 1-10' Trailing Ipomoea Vinca minor 12"-5' 9" Trailing Blue Vinca minor 'Maculata' 2-3' 12-18" Trailing Vinca minor 'Wojo's 18-28" 12-18" Trailing Gem' 2-3' 2-3' Trailing Vinca minor 'Illumination' 14-8 1106

Table 5. Annuals for sunny gardens. Abutilon, Flowering Maple 14-16" 12-24" Upright, Spreading Red, Salmon, Coral, Variegated Ageratum 12-30" 12-18" Mounded, Upright Blue, Violet, Pink, White Alstroemeria 10-18" 18" Upright, Mounding Rose, Red, White, Yellow, Bicolor Alyssum, Sweet 4-10" 12-18" Mounding White, Lavender, Pink, Rose, Purple Angelonia 14-30" 12-18" Upright White, Purple, Pink, Lavender Cut, Hummingbird, Slight Fragrance Fragrant Cut, Butterfly, Fragrant Asparagus Fern, 10-12" 12-18" Spreading Cut Sprengeri Fern Aster 12-30" 8-12" Upright White, Rose, Pink, Blue Cut Bacopa, Sutera 3-5" 12-24" Spreading, Trailing White, Lavender, Rose, Blue Begonia 'Angel Wing' 12-15" 15-18" Spreading, Trailing Red, Pink Begonia, Fibrous 8-12" 8-12" Mounding Red, Pink, Rose, White,, Bronze Hummingbird Bicolor Bidens 10-12" 24-36" Spreading Yellow Fragrant Black Eyed Susan, Thunbergia 2-6' 12" Vining Orange, Yellow, White Brachyscome 9-12" 9-12" Semi-Spreading Blue, Pink, Yellow Celosia 6-30" 9-15" Upright Red, Orange, Rose,, Bronze Cut Yellow Cleome 36-60" 15-24" Upright Cherry, Rose, Violet, Cut, Butterfly White Coleus, Vegetative 12-36" 12-24" Upright Multicolor 14-9 1106

Table 5 (Continued). Annuals for sunny gardens. Cuphea, Mexican Heather 6-9" 6-9" Mounding, Trailing Blue, Purple, White Dahlia 14-30" 12-18" Upright Burgundy, Orange, Red, Violet, White, Yellow Dianthus 8-24" 8-15" Upright Cherry, Coral, Violet, Pink, Purple, Rose, Salmon, White, Bicolor Dracaena Spike 12-18" 12-15" Upright Dusty Miller 8-12" 8-12" Mounding Silvery White Erysimum 12-15" 10-14" Upright Rose, Scarlet, Yellow Flowering Kale, 10-18" 15-18" Mounding Rose, Red, White Cabbage Gazania 8-10" 8-12" Mounding Bronze, Pink, Yellow, White, Pink Stripe, Red Stripe Geranium, Ivy 6-12" 18-30" Trailing Burgundy, Coral, Pink, Lavender, Pur;le, Red, Salmon, White, Bicolor Geranium, Martha Washington 12-18" 12-15" Upright Red, White, Pink, Purple, Salmon, Bicolor Geraniums, Seed 10-15" 8-12" Upright Cherry, Coral, Pink, Red, Rose, Salmon, Scarlet, Violet, White Cut, Hummingbird Cut, Butterfly, Some are Fragrant Geranium, Scented 12-18" 10-15" Upright White, Pink, Variegated Gereanium, Zonal 10-18" 8-15" Upright Cherry, Coral, Lilac, Pink, Hummingbird Purple, Red, Rose, Salmon, Scarlet, White, Bicolor 14-10 1106

Table 5 (Continued). Annuals for sunny gardens. Gerbera Daisy 10-18" 10-15" Mounding Apricot, Orange, Red, Rose, Salmon, Yellow, White, Violet Gomphrena 8-24" 10-18" Upright Pink, Purple, Red, White Cut Cut, Butterfly Grasses 12-48" 12-24" Upright Unique Heliotrope 10-14" 12-14" Mounding Purple, White Fragrant, Butterfly Hibiscus 12-48" 12-36" Upright Red, Orange, Pink, Fragrant, Yellow, White Butterfly, Hummingbird Hypoestes, Polka Dot Plant 8-24" 8-15" Mounding Pink, Red, White Lantana 12-18" 12-30" Spreading Lavender, Bronze, Yellow, White, Orange, Pink, Bicolor Lisianthus 10-40" 8-12" Upright Blue, Lavender, Pink, White, Bicolor, Variegated Butterfly, Hummingbird Cut Lobelia 6-12" 6-24" Upright, Spreading Blue, Lilac, Rose, White Marguerite Daisy, 12-24" 12-14" Upright White, Yellow, Pink Cut, Slight Argyranthemum Fragrance Marigold, African 8-36" 6-24" Upright Orange, Yellow, White, Bicolor Cut Marigold, French 6-15" 8-15" Upright Orange, Yellow, Bicolor Butterfly Melampodium 8-24" 8-15" Upright Yellow Million Bells, Mini Petunias, Calibrachoa 7-9" 12-24" Mounding, Trailing Blue, Pink, Yellow, White, Red, Cherry, Violet, Multicolor Morning Glory 6-12' 6-10" Spreading to Vining Blue, Pink, Red, Violet, Marbled Hummingbird, Fragrant 14-11 1106

Table 5 (Continued). Annuals for sunny gardens. Moss Rose, Portulaca, Purslane 8-15" 10-18" Mounding, Trailing Fuschia, Orange, Peach, Pink, Red, White, Yellow Nasturtium 8-12" 8-24" Mounding Yellow, White, Marbled Hummingbird, Edible, Fragrant Nemesia 8-15" 10-12" Upright Blue, Lavender, Rose, Red, White Nicotiana 10-28" 10-15" Upright Appleblossom, Lime, Pink, Red, Rose, White Nierembergia 6-12" 6-12" Mounding Purple, White Osteospermum 12-18" 12-15" Upright Blue, Magenta, Orange, Yellow, White Pansy 6-8" 6-12" Mounding Black, Blue, Red, Rose, Violet, White, Yellow, Blotch, Clear Penta 12-22" 10-14" Upright Cherry, Lavender, Pink, Red, Rose, Violet Persian Schield, Strobilanthus 36-48" 12-24" Upright Purple Petunia, Double 10-15" 12" Upright Burgundy, Orchid, Pink, Red, Rose, Salmon, White Petunia, Floribunda, Multiflora 10-15" 12" Upright Burgndy, Lilac, Blue, Orchid, Pink, Rose, Yellow, Red, Salmon, White Petunia, Grandiflora 10-15" 12" Upright Blue, Burgundy, Lilac, Pink, Red, Rose, Salmon, Violet, White, Bicolor, some Stars Fragrant Hummingbird, Cut Edible, Slight Fragrance Butterfly, Hummingbird Hummingbird Hummingbird 14-12 1106

Table 5 (Continued). Annuals for sunny gardens. Petunia, Hedgiflora 16-22" 12-15" Upright Cherry, Pink, Silver Hummingbird Petunia, Trailing 3-6" 36-48" Spreading, Trailing Blue, Lilac, Pink, Red,, Variegated Hummingbird Purple, Rose, White Petunia, Trailing Double 3-12" 18-48" Mounding, Spreading Blue, Lavender, Lilac, Pink, Purple, White Phlox 6-8" 6-10" Mounding Red, White, Blue, Salmon Plectranthus 3-6" 36-48" Spreading, Trailing, White Variegated Salvia 10-36" 8-24" Upright Blue, Burgundy, Lilac, Orange, Purple, Red, Rose, Salmon, White Sanvitalia 6-8" 6-8" Upright Yellow, Bronze Scaevola, Fan Flower 10-14" 18-24" Spreading, Trailing Blue, White Snapdragon 6-36" 6-12" Upright Bronze, Lavender, Pink, Purple, Red, Rose, White, Yellow Snapdragon, Trailing 6-8" 12-24" Trailing Bronze, Yellow, White, Orange, Pink, Purple Statice 12-30" 12" Upright Blue, Puirple, Rose, Salmon, White, Yellow Strawflower 10-14" 10-14" Upright Bronze, Pink, Yellow, White Sweet Potato Vine, Ipomoea 6-12" 12-30" Spreading, Trailing Black, Chartreuse Multicolor Some Fragrant Butterfly, Hummingbird Cut, Butterfly Butterfly, Hummingbird Cut, Fragrant Cut Sunflower 2-5' 12-18" Upright Red, Yellow Cut Tithonia, Mexican 28-30" 12-18" Upright Yellow Butterfly Sunflower Trachelium 12-40" 12-18" Upright Blue, Pink, Red, White 14-13 1106

Table 5 (Continued). Annuals for sunny gardens. Verbena, Upright 10-12" 8-12" Upright Blue, Burgundy, Lilac, Purple, Red, Rose, White Verbena Trailing, Spreading 4-12" 12-36" Spreading, Trailing Blue, Red, Pink, Purple, Lilac, Rose, White Vinca, Periwinkle 12-20" 12-24" Upright, Cascading Apricot, Orchid, Peach, Pink, Red, Rose, White Viola 7-8" 6-10" Mounding Black, Blue, Orange, Purple, Yellow, White, Bicolor Zinnia 8-36" 8-12" Upright Cherry, Orange, White, Pink, Scarlet, Coral Hummingbird Hummingbird Slight Fragrance Cut, Butterfly 14-14 1106