Fall Annuals

Josephs coat- Alternathera

Zone: 10-11

Light Requirements: Full Sun to Part Shade

Soil Preference: Medium moisture well drained soils

Pests/disease: None serious

Attributes: Alternathera has an inconspicuous bloom and is used as a foliar interest plant in the summer and fall garden. Brightly colored leaves are blotched with yellow, orange, red, or purple, the purple leaved being the most popular for fall. Alternathera grows 1-3’ depending on cultivar.

Our Experience: We use alternathera both in beds and containers, especially during the fall. Much like coleus during the summer, the contrast between the dark foliage of alternathera and the bright blooms of other fall annuals make for great eye-catching interest. 

Strawflower – Bracteantha

Zone: 8-10

Light Requirements: Full sun

Soil Preference: Average, dry to medium, well drained soils

Pests/disease: None serious.

Attributes: Strawflower is an annual with daisy like flowers which are straw like in texture (hence the common name) and so make great flowers for cutting and or drying. Common cultivars grow to 2’ and are very easy to care for and maintain. These short lived beauties work in beds, borders, containers, or as additions to the cutting garden.

Our Experience: We utilize strawflower most often in the fall due to its cold temperature tolerance, its aster like appearance, and its availability in a variety of colors (yellows, oranges, reds, pinks and white). We often mix strawflower in containers for a pop of bright color. While we have only experimented with the dwarf varieties of this plant, we hope to find a leggier selection in the future in order to incorporate this flower into our cut selections on Great Hill.

Ornamental cabbage and kale- Brassica oleracea

Zone: 7-11

Light Requirements: Full Sun

Soil Preference: Medium moisture well drained soils

Pests/disease: Slugs, aphids, caterpillars

Attributes: Ornamental cabbage and kale are used for foliar color during cool weather. Cabbage grows in heads of flat leaves while kale leaves are upright and curly. Both come in variations of white, pink, rose, red and purple. Grow 12-18”

Our Experience: Mainly used in fall beds and containers, kale and cabbage are fall standards- pairing nicely with your annual mums and seasonal grasses. When watering, avoiding the foliage helps to curb premature rotting of the plant. If the conditions are mild enough, these plants can often remain ornamental until well into November, their color intensifying as temps grow colder.

Heather- Calluna vulgaris

Zone: 4-6

Light Requirements: Full Sun to part shade

Soil Preference: Medium moisture well drained soils

Pests/disease: spider mites, scale

Attributes: Heather is a cool season evergreen shrub, utilized heavily as an annual in our zone due to its dislike of hot/humid summer temps, and its extremely picky personality. Heather does not like heavy soils but prefers sandy loam, needs full sun for better flowering, but prefers afternoon shade, and requires moist conditions that are not overly humid or areas exposed to winds. Heather have scale like green (turning bronze in fall) leaves on slender stems and pink, purple or white ornamental flower buds (some varieties open while some do not) from September through the fall. Grow to 24.”

Our Experience: While used as a groundcover or rock garden plant in areas its perennially suited to, we purchase heather annually as a fall ornamental. We’ve experimented several times with attempting to overwinter this plant with little/inconsistent success. Use heather in bedding areas or containers with good drainage and mulch with peat moss. Heather likes to be kept moist and pruned in the spring right before new growth appears. Avoid cultivating around the base of this plant as it’s roots are shallow.

Ornamental peppers- Capsicum annuum

Zone: 9-11

Light Requirements: Full Sun

Soil Preference: Medium moisture well drained soils

Pests/disease: leaf spot, root rot, aphids and whiteflies

Attributes: There are a range of ornamental pepper cultivars all growing between 1 and 4,’ and coming in an array of colors (yellow, red, purple, orange and brown). Plants in this species are quite varied, but grow in shrubby mounds, and, following flower, (small star shaped and white), feature attractive peppers that add both color and texture to fall annual displays.

Our Experience: We love using annual peppers in our fall containers on the hill. They are long lasting and compliment a variety of other annuals during cool fall months. Peppers are very low maintenance requiring only water, sunlight and good spacing for air flow.

Cockscomb- Celosia

Zone: 10-11

Light Requirements: Full Sun

Soil Preference: Medium moisture well drained soils

Pests/disease: Root rot, fungal leaf spot

Attributes: Annual celosia has a couple of different flower forms, the most widely used either having a long feathery bloom or a large crested flower head. Each of these types come in a variety of colors (red, orange, purple, pink or yellow) and vary widely in height growing from 8-36.” Celosias leaves are also ornamental being a mix of green/bronze and purple/red. Celosia bloom from late summer until frost and add texture and bold color to the fall garden.

Our Experience: When using celosia, be sure to plant in a bed/container with good drainage as these plants are prone to fungal issues. Celosia are a favorite to pair with other fall selections as they really stand out as other colors start to look a bit muted. Deadheading is a must to keep the blooms continuing until frost.   

Mum- Chrysanthemum morifolium

Zone: 5-9

Light Requirements: Full Sun

Soil Preference: Medium moisture well drained soils

Pests/disease: Aphids, spider mites, powder mildew and rot diseases

Attributes: Mums are typically purchased potted and prepped for use in the fall as annual color. While technically perennial in our zone, these plants are not reliably hardy, often perishing over the winter. Common garden mums are compact and clump forming. Flowers are solitary, come in a vast array of colors and often bloom from late September to frost. Leaves are deeply lobed and dark green. Grow 2-3.’

Our Experience: We have a love/hate relationship with “annual” mums on the hill. While they work well to provide bursts of color in fall bedding areas and or containers, their blooms are short lived (especially if it’s a warm fall). Planting and then removing these delicate (stems are very breakable!)  annuals within the span of two weeks or so is incredibly time consuming and high maintenance. Where you can, we’d recommend planting hardy perennial mums for fall color in your beds and borders. They’re available in a number of colors and heights to ensure they can be placed almost anywhere you need late fall interest.

Melampodium- Melampodium divaricatum

Zone: 9-11

Light Requirements: Full Sun

Soil Preference: Average well drained soils.

Pests/disease: None serious. Powdery mildew

Attributes: Melampodium is an annual in the aster family that produces daisy like yellow flowers (1″ across) and grows 6 to 12″ tall. Light green foliage grows on purplish stems. Used in pots or containers or as a bedding annual.

Our Experience: We use melampodium as a fall annual on Great Hill as stems tend to flop in the heat of the hot summer months. Bright pops of yellow color contrast nicely with darker fall selections.

Pot Marigold- Calendula officinalis

Zone: 9-11

Light Requirements: Full Sun

Soil Preference: Average well drained soils.

Pests/disease: None serious. Powdery mildew, aphids.

Attributes: Calendula is an annual herb in the daisy family thats often utilized either in the spring or in the fall due to its intolerance of the hot and humid weather. It grows 1 to 2′ tall and wide and features daisy or chrysanthemum like bright yellow or orange flowers 3 to 4″ across. Cultivars widen the color margin to pastels as well as double flowers and bicolors. Although flowers and leaves are bitter tasting, both are edible and aromatic often added to salads, soups and rice dishes.

Our Experience: We commonly use calendula in our fall bedding and container arrangements on Great Hill. Newer cultivars tote tolerance to the heat and humidity of the summer, but in testing them, we’ve found that while they do not die completely, they certainly don’t flourish during the heat of the summer. If attempting to stretch calendula from spring to fall, be sure to plant them in an area that gets afternoon shade and or some sort of protection from the direct sun.