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Achillea is commonly referred to as yarrow is a genus with about 85 species of deciduous perennials from temperate regions of the N. hemisphere. A huge variety exists but generally they prefer moist but well-drained soil in and open site, full sun. Aphids may be a problem as well as powdery mildew.

Ageratum (as seen in the perennials picture), is commonly called floss flower is a genus of about 40 species of annuals, perennials and shrubs found naturally in diverse habitats in tropical and temperate areas of North and South America. Ageratum bears small rounded flower heads, 30 - 50 per stem, often in muted shades of blue, white or pink. A great plant for late season flowers, adapts well to containers or beds and borders. Ageratum likes fertile, moist, well-drained soil, full sun to part shade. Sow seeds in the spring or autumn. Generally, if grown in the northern zones more pest free, but still subject to powdery mildew and rust during dry seasons and blight is a problem during cool, wet weather. The plant itself resembles mint until bloom time.

Alcea, commonly called hollyhocks is a genus of about 60 species of biennials and short-lived perennials naturally found in temperate grassland or rocky regions of Europe and Asia. Cultivated for their double flowers either on short or tall stalks. Remarkably easy to grow they need moderately fertile soil full sun. Prone to hollyhock rust this genus is remarkably pest free once past infancy. Height expected is 4' to 6' and hollyhocks naturally reseed

Alchemilla is a genus of about 250 species inhabiting meadows and woodland areas. Commonly called lady’s mantle it is found in temperate arctic zones and mountain regions from tropical Africa, India, Sri Lanka and Iceland, the Carpathian and Pyrenees Mountains as well as Indonesia. Lady's mantle is valued for their wonderful bright yellow-green foliage and frothy sprays of flowers definitely highlighting that shady spot. They like humus rich, moist soil, partial shade. Cut back after flowering because this is another plant that freely self-seeds. Slugs and snails may do damage when leaves are young and tender, but otherwise disease free and hardy. Cultivars may be clump forming or mat forming and lady's mantle makes and excellent groundcover or splendid addition to a rock garden. Many are drought tolerant and cut flowers are especially long lasting.

Anemone is a genus of about 120 species of perennials found worldwide and they are commonly called windflower. Grown for their open saucer-shaped flowers their show runs from late summer into fall. Cultivars that originate from the Mediterranean and Asia generally flower in spring or early summer. Because of the difference in origin cultivation requirements are specific for cultivars but generally moist, humus-rich soil, sun to part shade. Propagation is from seed in containers and a cold frame as soon as the seeds are ripe, divide autumn-flowering anemones in early spring or autumn, and take root cuttings in spring. For spring flowering anemones separate tubers in summer when dormant. All are prone to mildew, smut and rust, nematodes, caterpillars, slugs and beetles.

Anthriscus is best known by the common name of Queen Ann’s lace and the genus contains about 12 species of annuals and perennials that grow naturally in wasteland, woodland and grassland areas of the N. hemisphere. Propagation and pests not worth mentioning.

Aquilegia, commonly called columbine, is a genus of about 70 species of perennial plants native to meadows, woodland and mountainous regions of the N. hemisphere. They like fertile, preferably moist, well-drained soil, and full sun to full shade. Divide in early spring or in the fall. Susceptible to mildew and rust a particular favorite of aphids, leaf miners and caterpillars.

Asclepia aka butterfly weed commonly called milkweed is a genus of about 110 species of perennials, shrub and sub shrubs beloved by butterflies. Naturally found in temperate grasslands, marsh and scrub areas of the western hemisphere. They like fertile well-drained soil full sun. Propagation is by seed in spring or division in spring or fall. May be prone to whitefly, mites and aphids, fungal and bacterial problems as well, you may want to choose not to treat asclepia as it will transfer poison to the caterpillar.

Aster is a genus that contains about 250 species of annuals, perennials and sub shrubs found naturally in a variety of habitats from mountainous sites to moist woodlands, all but a few are native to North America. Aster's daisy-like flower heads are borne on branched stems and there is a cultivar suitable for almost every garden site. Cultivation requirements are as diverse as are the many cultivars, generally speaking well-drained fertile soil, and full sun to part shade. Asters are among the best of the late-summer perennials offering a wide range of color. Give asters plenty of space in the bed as they may be prone to mildew, wilt, gray mold, rusts, fungal leaf spots, and smut. Mites attack, as do slugs, snails, nematodes, blister gall and aphids. Sow seeds in containers in spring or autumn, or divide and separate preferably in spring. Once established, hardy asters can overrun the garden, as this native American does not lack spunk. To harvest and condition, strip off the leaves, the flowers firm up nicely in warm to hot water.

Astilbe is a genus of about 12 species of densely clump-forming perennials found naturally in moist sites, mountain ravines, woodland areas of SE Asia and North America. Astilbe are grown for they’re striking, plume-like flowers now available in just about every color. All cultivars flower heads turn brown in autumn and provide interest through winter. A great cut flower but again too, the color will fade. The foliage is attractive if you choose not to have brown flowers remain. Astilbe likes moist, humus rich soil or boggy sites full sun or part shade. They do not like clay or alkaline soil that dries out in summer. Divide and replant every 3 - 4 years to maintain vigor and flower quality. Best advice is to divide in early spring when dormant. Prone to powdery mildew and bacterial leaf spots.

Boltonia is another taller genus of native American aster-type flower heads but this genus only has 8 species. Please check aster for further information

Clematis is a genus of more than 200 species of evergreen and deciduous perennial climbers. Found naturally in a variety of spots throughout the N. and S. hemispheres. They like fertile, humus rich, well-drained soil, full sun or part shade. Pruning is essential with all clematis and guidelines are very cultivar specific based on whether they bloom on previous years shoots or current season growth. Prone to scale, whiteflies, earwigs and aphids, wilt powdery mildew; rust, fungal spots and cankers are common.

Convallaria commonly called lily-of-the-valley is a genus of 3 species found naturally in woodland, scrub and alpine meadows in northern temperate regions. Pendent, bell-shaped, fragrant, mostly white flowers, is the attraction; a hardy groundcover enhances its appeal. Convallaria like humus-rich, moist soil, full sun or full shade. Divide pips in autumn keeping the soil moist until established. This genus is virtually pest and disease free.

Campanula is a genus of about 300 species of annuals, biennials and perennials found naturally throughout the N. hemisphere in very diverse habitats from high alpine rock crevices to moorlands, meadows and woodlands. The habits range from low tufted mats, dwarf, or trailing, to tall and upright. The flowers are tubular, bell-shaped or star-shaped and haven't a scent worth noting.  Obviously soil requirements vary depending on the species and habit but full sun to part shade, well drained will suffice. All will reseed profusely so best bet is to cut back after flowering. Prone to slugs, snails, weevils, mites and aphids. Powdery mildew, rust, blights may be a problem. Color ranges from deep purple to light blue, soft pink or white. Commonly called bellflower taller cultivars may need staking.

Chelone, commonly called turtlehead, is a genus of about 6 species of perennials native to moist woodland, prairies and mountainous areas of North America. Bearing white, pink, or purple flowers in late summer early fall it is a showy, sturdy plant. Cultivar height is between 2 and 4 feet making this a great statement to the late blooming garden. Turtleheads like fertile, moist soil, an open site, full sun to part shade, more good news they will tolerate heavy clay soil and give a good performance. Propagation is by seed in containers and a cold frame early spring, or division at that time as well. Root softwood cuttings late spring early summer. Prone to mildew, rust, and fungus and enjoyed by slugs and snails in the spring.

Chrysanthemum is complex genus with categories and subcategories, twelve different flower head distinctions with a further breakdown as to flowering time. Then they are even more minutely identified further into five more classifications. Generally gardeners think of non-disbudded chrysanthemums, which means we allow them to grow freely and they grow in sprays and produce several blooms per stem in a variety of blossom forms. They flower over a long period of time and are suitable for beds and border, wildflower and rock gardens, containers and all are excellent for cutting. They like full sun, fertile, moist but well-drained soil. Provide support if your mums are excessively tall with soft twine and stakes. Water freely in dry weather and apply a balanced liquid fertilizer every month. Propagation is from seed in the late winter or spring. Divide in spring. Prone to aphids, earwigs, nematodes, miners, mites and whitefly. Susceptible to fungal rot, mold, mildew and white rust. Viruses may cause stunting, yellow markings and puckered leaves.

Coreopsis is commonly called tickseed and is a genus of about 100 species of softly hairy annuals and perennials. Naturally found on prairies and in woodlands throughout the Americas and Mexico these daisy-like flower heads are bone on long stalk and generally are long lasting when cut. Coreopsis likes full sun to part shade, fertile well-drained soil, taller cultivars may need staking, deadhead to prolong flowering. Propagation is from seed in situ, or division in early spring. Slugs and snail feed on this plant so beware, bacterial spot, rust, mildews and fungal spots may occur.

Delphinium is a genus of about 250 species of annuals, and perennials found in mountainous regions worldwide except Australia. Delphiniums like fertile well-drained soil, full sun and protection from strong wind. Feed every 2-3 weeks with a balanced fertilizer starting with spring growth. Plagued with problems like slugs, snails, mites, mildews, blight, bacterial and fungal spots, mold, crown and root rot, rust, smut and damping off.

Dianthus is a huge genus with over 300 species of mostly evergreen, low growing annual and biennials found naturally in meadows and mountains in Europe, N. Asia and Japan. Cultivars number in the tens of thousands; bred for commercial and garden use this is a genus to specialty shop. There are five different flower classifications for carnations and pinks, the flowers are usually clove scented and long lasting when cut. They bloom in profusion over long periods from late spring into summer.  Most species and cultivars prefer full sun, well-drained soil, lightened a bit with sand. Take care when planting and do not bury the lowest leaves and be mindful of the feeder roots. It seems every pest is fond of carnations; slugs, grasshoppers, chipmunks, squirrels and deer can be problems as well as rusts, rots and fungal diseases. Propagation is from seed in a cold frame from fall to early spring, cuttings and division best bet.

Dicentra or bleeding heart is a genus of 20 or more species of annuals and perennials native to Asia and North America, naturally found in moist habitats including woodland and especially mountainous regions. The perennial species is often rhizomatous or tuberous in nature with fleshy taproots. The leaves are delicate and often fern-like, sometimes silvery gray. Pendant heart shaped flowers in red, pink, white, purple or yellow borne on arching panicles. Excellent woodland plants or in a shady border dicentra likes humus-rich soil, neutral or slightly alkaline. Prone to downy mildew, viruses, and a favorite of slugs and snails when growth is beginning.

Digitalis is a genus of about 22 species of biennials and perennials naturally found in Europe, NW Africa and C. Asia in open woodland areas, meadows and grassy slopes. They like humus rich soil not too wet and not too dry in a part shade setting. Propagation is by seed in situ or division in spring or autumn, feed during bloom set. Prone to southern blight, anthracnose, and fungal leaf spots. All parts of this plant if ingested may cause severe reaction and contact with foliage may irritate skin.

Draba is a genus of about 300 species of mat or cushion-forming perennials found naturally in cold temperate regions of South America often in rocky or mountainous areas. A great species for rock and alpine gardens. This genus spreads slowly blooms profusely and has wonderful little, thick dark green leaves. Draba likes full sun and gritty well-drained soil. 

Echinacea commonly called coneflowers is another one of those plants to be wary of. This is a genus of about 9 species of perennial found naturally in prairies, open woodland and hillsides of North America. The daisy-like flower heads are a wonderful addition to the late summer garden. Echinacea likes deep, well-drained rich soil, full sun but will tolerate a bit of shade. Propagation is by seed or division in spring, root cuttings late autumn. Encourage reblooming by deadheading and to prevent excessive self-seeding. Leaf miners, powdery mildew, mold and bacterial spots may be a problem.

Erigeron commonly called fleabane is very similar to an aster. The difference is the set of the flowers on the stem and erigeron grows to a shorter overall height but otherwise very aster-like. Erigeron is a genus of over 200 species of annuals and perennials and is another native American. Grown for their late blooming daisy-like flower heads and like asters they too are prone to mildews, smut, and blight. Care during the growing season is the same and it is recommended to cut back to ground level in autumn to retain neat growth. .

Eupatorium is a genus of over 40 species of perennials occurring naturally in dry sandy conditions, woodland, pastureland and swamps just about worldwide. More recognized by the common names as Joe Pye weed, snakeroot, boneset and mistflower. Whatever the common name given a species eupatorium bears nectar-rich flowers beloved by butterflies and bees. All like moist soil full sun divide hardy species in the spring. Prone to rust powdery mildew, and smut.

Geum is a genus of about 50 species of perennials native to streamsides, moist meadows and woodland areas throughout the Northern hemisphere. Grow in fertile, well-drained soil, full sun. Propagation is by seed either in spring or autumn. Prone to downy mildew, powdery mildew and smut.

Heuchera, commonly called coral flower, is a genus of about 55 species of evergreen and semi-evergreen perennials found naturally in woodland settings in North America and Mexico. Grow in fertile, well-drained soil, sun or part shade. Susceptible to mildew and rust.

Iberis is the genus but more commonly called candytuft and contains about 40 species of annuals and perennial plants native to soil with high calcium carbonate content, otherwise known as chalk. Propagation is from seed in situ in spring or autumn. Prefers cooler weather for blooms iberis will generally bloom again in the fall. No pests or problems of note.

Kniphofia, commonly referred to as red-hot-poker is a genus of about 70 species of evergreen or deciduous rhizomatous perennials found naturally in moist places in southern and tropical Africa. They prefer humus-rich soil, full sun. Basically disease and pest free.

Ligularia is a genus 150 species strong of robust, often coarse perennials mostly from C. and E. Asia. Found naturally in moist or wet grasslands, moist scrub and woodland areas. Ligularia likes moderately fertile soil with moisture, full sun or part shade. Basically pest and disease free snail and slugs may attack tender new growth.

Linaria commonly called toadflax is a genus of about 100 species of annuals, biennials and perennials naturally found in temperate regions of the N. hemisphere. The flower is 2-lipped, spurred, in white, pink, red but most common in shades of purple with a yellow center and resembles a single snapdragon with non of its lovely manners. Toadflax likes moderately fertile and sandy soil full sun. Aphids, flea beetles, downy mildew, and smut may be a problem. Sow seed in situ early spring

Lobelia is a genus of about 370 species of annuals and perennials and shrubs found worldwide. Given the multitude of species lobelia's habitat ranges greatly from marshes, meadows, woodland areas, mountainous slopes to desert regions. Lobelia varies from species to species too, but all have brightly colored flowers, simple alternate leaves and 2-lipped, tubular flowers. Lobelia likes deep fertile soil, full sun or part shade, and they enjoy heavy feeding. Propagation is by seed in late winter or division in spring. Prone to rust, smut, leaf spot and slugs.

Lupinus is a genus of about 200 species of annual, and perennials naturally found in the Mediterranean, N. Africa and the Americas in dry, hilly grassland, open woodland, coastal sands and riverbanks. Lupines grow best where summers are cool and soil is fertile, light and slightly acidic and well-drained, full sun or part shade. Propagation is in spring and in-situ, but nick the seed and soak for at least 24 hours before planting. Prone to fungal and bacterial spots, mildews, rust, stem rot, and blight.

Malva or commonly called mallow is a genus of about 30 species of annuals, biennials and perennials found naturally in dry, open areas and roadsides of Europe, and N. Africa, naturalized all over. They require moderately fertile soil, full sun. Malope is called annual mallow and sidalcea is called false or prairie mallow, each is similar in appearance and requirements.

Monarda is commonly called bee balm, and is a genus of about 15 species of annuals and clump-forming rhizomatous perennials naturally found in prairies and woodland setting throughout North America. Monarda likes moderately fertile, humus-rich moist soil full sun or dappled shade. Divide mature clumps before new growth begins in the spring monarda can be somewhat aggressive. Especially prone to powdery mildew, rust and leaf spot may be a problem.

Oenothera is commonly called evening primrose or sundrops and is a genus with about 125 species of annuals and perennials found naturally across North America and a few in South America. Adaptable to most any sunny location in poor to moderately fertile soil. Mildew is the most common problem.

Omphalodes is a groundcover related to Forget-me-nots. Bicolor flower of vivid true blue and white against green foliage grows by creeping and spreading. 6-8 inches high, 15 - 18 inches wide.

Papaver is a genus of 70 species of annual, biennial and perennials naturally occurring on every continent except South America.  All species exude latex when damaged; generally all are short lived, with tissue paper fine petals, elaborate interiors and distinctive seedpods. All like well-drained soil full sun. Sow seeds in spring for all, divide in early spring and take root cuttings in late autumn or early winter. Prone to powdery mildew, leaf smut, and mold, but not bothered by pests.

Parthenocissus is better known as Boston ivy or Virginia creeper and the genus contains about 10 species of deciduous tendril climbers naturally found in the forest of E. Asia and North America. They like fertile well-drained soil sun or shade. The list of pest and diseases is long but not threatening.

Perovskia better known as Russian sage is a genus of 7 species of sub-shrubs that occur naturally in Asia to the Himalayas. Grown for their flowers that smell a bit like lavender. Not bothered by pests and tolerant of most soils, grow full sun to part shade. Propagation is by softwood cuttings in late spring.

Physostegia is a genus of 12 species of erect deciduous perennials native to the eastern areas of North America commonly called obedient plant. The tubular lipped flowers are borne on almost stalkless stems. They like fertile, reliably moist soil, full sun to part shade. Division is in winter or early spring before new growth appears. Rarely affected by pest and diseases this rhizome will run rampant and become invasive if allowed space.

Primula is a genus of about 450 species of herbaceous perennials found naturally in bogs, marshlands and alpine areas worldwide. The zone very often dictates the sun requirements, all but the most northern, part shade. Soil should be moist, humus rich, and gritty. In growth water and feed freely, sow seeds late winter in containers, divide in early spring. Prone to aphids, mites, slugs, mold, root rot and rust.

Prunella commonly known as selfheal is a genus of 7 species of spreading perennials that root very freely at the node. Naturally found on dry grassland, open woodland and sunny banks in Asia, Europe, and North Africa and throughout North America. Any type of soil will do full sun or part shade. Powdery mildew may be a problem.

Rudbeckia commonly called black-eyed-Susan is a gnus of about 20 species of annuals, and perennials native to North America. Not particular about soil, moderately fertile will do, full sun or part shade. Sow seeds in early spring divide in spring or autumn. Slugs and snails like tender young growth, aphids, powdery mildew, rust and smut may occur.

Salvia is a genus with about 900 species of annuals and perennials, shrubs and tubers. Salvia is found naturally worldwide usually in sunny sites, dry meadows and grasslands and rocky slopes. Flowers are basically two-lipped and funneled but that is where the similarities end and the difference of the cultivars come into play. They like moderately fertile, well-drained soil, full sun to light dappled shade. The hairier the cultivar the sharper the soil should be cut with sand, plant in full sun. Protect hardy salvia from excessive winter moisture. Propagation is by division in spring, sow seeds after all danger of frost, or take basal root cuttings in spring and early summer. Prone to rust powdery mildew, stem rot, and fungus are common. Pests include whitefly, aphids, mealy bugs and spider mites.

Saxifraga is a huge genus of about 440 species or cushion forming, evergreen perennial found naturally in the N. hemisphere. They vary greatly in habit and form but generally star shaped or cupped flowers. Depending which cultivar defines the specific cultivation requirements but fertile well-drained soil, full sun to part shade. Best propagation is by division or detach individual rosettes and roots in late spring. Aphids, slugs, and mites may occur.

Sedum contains over 400 species of succulent annuals, evergreen and deciduous, perennials, shrubs and sub shrubs and groundcovers, some of which even crossover to other genuses. Native to the N. hemisphere this species goes way beyond the "common" garden sedum to include succulents like burro's tail and stonecrop. Outdoor varieties need moderately fertile, well-drained soil, full sun. Cut back spreading species after flowering and divide larger species every 3 - 4 years. Sow seeds of hardy species in a cold frame in autumn. Annuals and biennials sow seeds in midspring. Mealy bugs, scale, slugs and snails may be problems.

Solidago commonly called goldenrod contains about 100 species of woody-based perennials native to North America. Most species are course and invasive and are best grown in a wild setting some cultivars are suitable for a rock garden. Goldenrod flourishes in poor to moderately fertile soil, full sun. Remove spent flower heads, as this is a vigorous reseeder. May be prone to powdery mildew and rust.

Tradescantia commonly called spiderwort is a genus of about 65 species of creeping, trailing or tuft-forming, tuberous-rooted, evergreen perennials native to woodland areas in North, Central and South America. They prefer moist, fertile soil in full sun or part shade. May be affected by viruses, aphids and spider mites.

Trollius is a genus of about 24 species of buttercup like perennials naturally found around moist or wet meadows in North America, Europe and Asia. Grow in moist, heavy, deep, fertile soil that does not dry out, full sun or part shade. Cut stems back hard after the initial bloom and provide a balanced fertilizer throughout to encourage reblooms. Propagation is in spring in situ when the pod is ripe, although the seed may take two years to germinate. Powdery mildew may be a problem.

Viola is a genus of about 500 species of annuals and deciduous perennials found in a variety of habitats worldwide. Many are informally referred to as pansies, violas or violets. They like fertile, humus rich, moist, gritty soil, full sun or part shade. After blooming deadhead after flowering cut back. Propagation is from seed in late winter or division. Prone to mosaic viruses, mildews, crown and root rot, rust and mold, snails and slugs and aphids as well.

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