problem solver

Tall buttercup
Ranunculus acris

IDENTIFICATION — According to folklore, if your skin glows yellow when you hold a buttercup under your chin, you love butter. But that doesn’t mean you have to love tall buttercup!

Although it looks similar to several native buttercups, this invasive perennial was introduced from Europe, and is now widespread throughout the United States and Canada. Also known as “blister plant,” tall buttercup contains a noxious oil that can blister the skin.

Its branched stems grow 1 to 3 1/2 ft. tall, and end in branched clusters of glossy, five-petaled yellow flowers. The flowers, which bloom from May to September, are only about 1 in. in diameter.

FAVORITE CONDITIONS — Tall buttercup prefers moist soil, so you’ll rarely find it where the ground stays dry. In fact, it often grows in low spots that stay wet, such as roadside ditches and stream banks. You’re more likely to find this weed in shrub borders or established perennial beds than in heavily cultivated areas. It spreads quickly and easily, often crowding out other plants

CONTROL — Because tall buttercup spreads by seed, control is easiest when plants are young and haven’t had time to set seeds. The roots are often shallow, but dense. Dig or pull this weed out by hand, but make sure to wear gloves so the blistering sap doesn’t get on your skin. You can also remove young weeds with a sharp hoe. A thick layer of mulch will help prevent seeds from germinating.

Broadleaf herbicides like 2,4-D and Roundup^® are also effective. Apply them before tall buttercup has a chance to flower and set seeds — you’ll have a much better chance of getting rid of this pesky weed.

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Wild grape
Vitis spp.

IDENTIFICATION — Long, twining vines wind their way into shrubs and trees. As the stems mature, the bark peels into narrow strips. Older vines produce clusters of small dark purple fruit in late summer.

FAVORITE CONDITIONS — Wild grape prefers sun to part shade in any type of soil, either moist or dry. It has an unlimited spread because the vines root wherever they touch the soil. The spread is helped by birds, which eat the messy fruit. Large thickets of vines can shade out or even kill mature shrubs and trees.

CONTROL — When the plant is a seedling, pull or dig it out of the ground. If it’s too large for this, spray the plant with a nonselective herbicide, such as Roundup^® Poison Ivy & Tough Brush Killer Plus in spring or late summer. Or cut down the tree and dribble or brush on a systemic stump killer around the edges where the sap is flowing. It’s absorbed into the wood and kills the roots. Be careful — it can kill any plant it gets on.

Click image to see a close-up of the leaves.

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Siberian elm
Ulmus pumila

IDENTIFICATION — Remember American elms? The leaves of this 50- to 70-ft.-tall, 30- to 50-ft.-wide woody weed look similar. However, they’re usually smaller and riddled by insects. In spring, before the leaves even open, you’ll spot clusters of pale-green flowers on the branches. Later, usually by early summer, large quantities of small papery disclike seeds begin to fall. They are spread by the wind, sprout and grow very quickly. Siberian elm trees have weak wood, so you’re constantly picking up the fallen twigs and branches.

FAVORITE CONDITIONS — You’ll find Siberian elm growing in full sun to part shade in moist to average soil.

CONTROL — When the plant is a seedling, pull or dig it out of the ground. If it’s too large for this, spray the plant with a nonselective herbicide, such as Roundup^® Poison Ivy & Tough Brush Killer Plus in spring or late summer. Or cut down the tree and dribble or brush on a systemic stump killer around the edges where the sap is flowing. It’s absorbed into the wood and kills the roots. Be careful, it can kill any plant it gets on.

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Bull thistle
Cirsium vulgare

IDENTIFICATION — Common throughout much of North America, bull thistle is a biennial that reproduces only by seed. The seeds sprout in fall or spring. First-year plants are a low rosette of leaves that can grow as large as 3 ft. in diameter, although they’re usually smaller.

A second-year bull thistle is from 2 to 6 ft. tall by midsummer when it blooms. The flowers are 1 to 2 in. in diameter, deep purple to bright pink and fuzzy. There are spines along the stems, the edges of the long leaves and the midrib of each leaf. And the underside of the leaf is silvery-white.

After the blooms fade, the flower head seems to close up and a white fuzz appears at the tip. Soon, the “bud” reopens to release the seeds. Each tiny, brown, striped seed has a bit of white fluff attached that helps it drift on the wind to a new location.

FAVORITE CONDITIONS — This is an aggressive weed with a long taproot that will grow in almost any soil. It needs a place where it can complete its two-year life cycle undisturbed, so you rarely find it in areas that are regularly cultivated, such as vegetable gardens or annual beds. Lawns, shrub and perennial borders, as well as fencerows, ditches and garden edges, are where it grows best.

CONTROL — The easiest control method is to cut the entire plant down to the ground just before it blooms. If you cut first-year rosettes or older plants too early in the season, the root can resprout and flower. Even flowering stems that are cut and lying on the ground can produce viable seeds, so burn or bury them. For serious infestations, glyphosate or 2,4-D herbicides are effective if you spray first-year rosettes in the spring or fall.

Take care of lots of weeds with the Handy Weeder/Cultivator at right!

problem solver

Tree of heaven
Ailanthus altissima

IDENTIFICATION — Crush the leaves of tree of heaven and you’ll pick up a foul, skunky odor. The leaves are large, sometimes growing to 3 ft. long. Each leaf is made up of many pointed leaflets. New leaves often have a red tint before changing to bright green. This pest quickly grows up to 75 ft. tall with a 3-ft.-diameter trunk. Wind-blown seeds sprout and grow anywhere. Short-lived, averaging only 25 to 30 years, the weak wood breaks easily in storms. And toxin in the bark and leaves can keep seeds of other plants from sprouting.

FAVORITE CONDITIONS — Tree of heaven grows in sun or part shade in any type of soil, including rubble piles or cracks in cement.

CONTROL — When the plant is a seedling, pull or dig it out of the ground. If it’s too large for this, spray the plant with a nonselective herbicide, such as Roundup^® Poison Ivy & Tough Brush Killer Plus in spring or late summer. Or cut down the tree and dribble or brush on a systemic stump killer around the edges where the sap is flowing. It’s absorbed into the wood and kills the roots. Be careful — it can kill any plant it gets on.

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Hemp dogbane
Apocynum cannabinum

IDENTIFICATION — Like an alien in a science fiction movie, the roots of hemp dogbane keep spreading as if they’re going to take over the world. Their long horizontal roots can spread more than 20 ft., eventually forming colonies that will squeeze out other plants.

The red-brown stems of hemp dogbane, sometimes known as “Indian hemp,” “bitterroot,” “rheumatism weed” or “Choctaw-root,” can grow up to 6 ft. tall. While young, the plant looks a bit like a milkweed. If you break the stem or leaves, you’ll discover a milky white sap, which is toxic if ingested. Small bell-shaped pale-green flowers bloom in clusters near the tips of the stems from June to August. Later, two 2- to 4-in.-long seed pods replace each flower. These pods are filled with tiny brown seeds that have tufts of white fuzz to help them float on the wind.

FAVORITE CONDITIONS — Hemp dogbane can be found in fields, thickets and open woods all over North America. It prefers moist soil, but once it’s established, the extensive root system makes it quite drought tolerant. In home gardens, you’re most likely to find it in shrub borders, low areas, like ditches, and in fence rows. You’ll rarely see this weed in garden areas that are regularly cultivated.

CONTROL — Working the soil repeatedly will help control hemp dogbane. Till young plants under before they reach 10 in. tall and have a chance to become established. If you can turn the soil and expose the roots during hot and dry weather, those roots will be less likely to resprout. You’ll need to till the area several times a year, and over a period of years, to eradicate all of the roots.

Because it’s such an aggressive spreader, hemp dogbane is most quickly controlled with herbicides, such as 2,4-D or Roundup^®. Apply them in the spring when the plant is just beginning to bloom or in late summer before the leaves turn yellow.

Click image to see a close-up.

problem solver

Yellow woodsorrel
Oxalis stricta

IDENTIFICATION — If yellow woodsorrel has something to lean on, it can grow to be 20 in. tall. But it’s usually more mounding to sprawling. It has tiny yellow flowers almost all of the growing season. Each leaflet is shaped like a small heart and folds up at night. When touched, the ripe seed pods explode to shoot the seeds great distances.

FAVORITE CONDITIONS — You’ll find yellow woodsorrel in flower beds, lawns and even containers. It grows in most any kind of soil, but tends to be less aggressive in fertile soil. And it tolerates both sun and shade.

CONTROL — The stems break easily, making it difficult to pull. But if you do it when the soil is moist, it’s much easier and you’re more likely to get all of the roots out. It’s easier to hoe out the shallow roots, and large areas of it can also be controlled by herbicides. This perennial spreads by seeds and underground rhizomes.

PHOTO: John Holtorf

problem solver

Ground ivy
Glechoma hederacea

IDENTIFICATION — Ground ivy, also known as creeping Charlie, is a perennial weed that spreads by seeds and above-ground runners. Each runner can be several feet long, with many leaf nodes along the stem. Wherever these nodes touch the soil they take root quickly to form thick, dense mats.

In midspring to early summer, purple flowers completely cover the plant. The foliage is small with a scalloped edge and if crushed, it gives off a strong minty smell.

FAVORITE CONDITIONS — You’ll find ground ivy’s at home in lawns or areas that are occasionally tilled. Moist, shaded spots are perfect for it, but it’ll tolerate almost anything, from full sun to dry, compacted soil.

CONTROL — In flower and vegetable gardens, pulling and hoeing are effective. Just make sure to pick up all of the pieces. Any part that’s left behind can grow a new plant. Once you get ground ivy under control, you’ll want to keep it from creeping back into gardens from neighboring areas. It’s a good idea to maintain a strip of bare soil around your garden where you can patrol occasionally and remove runners before they spread.

Since ground ivy can’t grow as fast in tall grass, set your lawn mower blade high. You can also use selective herbicides that won’t harm your lawn. Look for products containing dicamba, such as Acme Trimec ^® or Weed-B-Gon Lawn Weed Killer2 ^®. Read the instructions, but in severe infestations you may need to make at least two applications about 10 to 14 days apart to get rid of ground ivy.

five tips for a
weed-free path

A good way to make a garden more easy-care is to grow plants close together. This tends to shade out weeds, and any that do take hold are spindly and easy to pull. Bricks set tightly together in a path or patio make it hard for weed seeds to grow there, too. But no matter how tightly bricks are packed together, weeds seem to find their way between the crevices. Here are five tips to keep them from taking over.

SKIP THE FABRIC — When installing a path, save yourself the cost of landscape fabric. Most of the weeds that grow between bricks are the result of seeds taking root at the surface, not roots coming up from below.

PUT DOWN A BARRIER — Keep seeds from germinating with a corn gluten meal pre-emergent herbicide. Follow label directions and sprinkle it on the pavers. Work it into the crevices with a broom because corn gluten needs to be in contact with soil to work. Then water it in. Corn gluten can stain some surfaces if you let it sit, so test a small area first before putting it down.

USE THE RIGHT TOOL — You don’t need to buy any special tools. Use what you already have around the house to make weeding easier. A pair of needlenose pliers and an old paring knife are great for getting weeds out of tight places. See how the pliers in the photo keep your knuckles from getting skinned up on the rough brick? Use the knife to loosen stubborn weeds in narrow spaces. (The Soil Knife at right is one of our favorite weeding tools.)

SPRAY SOME VINEGAR — Did you ever think that weeding could be as easy as a few squirts of vinegar? It’s true. The USDA has studied various concentrations of vinegar for use in organic farming, and found that even the stuff you have in your cupboard works to kill small weeds. Be careful using it around ornamental plants, though, as it will burn the foliage. If the weed happens to pop up again, get out your spray bottle. Another application should do the trick.

GET OUT THE TARP — To avoid spreading seeds as you weed the garden, lay a tarp down on the bricks first. Then pull it along with you as you get rid of unwanted plants.

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Foxtail barley
Hordeum jubatum

IDENTIFICATION — Growing up to 3 ft. tall, this upright grassy weed has wispy seedheads that look iridescent in the sunshine. Foxtail barley spreads by seeds and roots. Each seed has wiry bristles with tiny barbs that grip onto clothing or fur to help it travel to new locations.

FAVORITE CONDITIONS — Foxtail barley can grow almost anywhere with full sun and well-drained soil.

CONTROL — Dig this perennial from the soil or apply a non-selective herbicide in the spring as the flower heads begin to show.

Click image to see lookalikes.

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Poison ivy
Toxicodendron radicans

IDENTIFICATION — Just about every gardener’s least favorite weed! Not only does poison ivy grow and spread rapidly, but it gives many people an itchy, sometimes painful, rash. This woody weed can have an upright form up to 7 ft. tall or appear as a climbing vine, hanging on to trees or fences with dark aerial roots.

The three leaflets, which are sometimes shiny, have a wavy edge and a reddish cast and stem. Insignificant green-white flowers appear in late spring, followed by fruit that ripens about the same time the leaves turn red in fall.

FAVORITE CONDITIONS — Poison ivy prefers moist, rich soil in full sun to part shade. You can find it along roadsides, in wooded, moist or wet areas.

CONTROL — To pull or cut back the plant, be careful to keep urushiol, the sticky oil that is present in all parts of the plant, off your skin. Wear long pants, long sleeves and double gloves. If you don’t want to handle it, spray the plant with a systemic herbicide like Roundup^®, but it’ll take time and several applications to eradicate it. You can also dab or spray the cut ends of the vine with a systemic brush killer (again, a herbicide that contains triclopyr is best.)

LOOKALIKES — Another sneaky thing about poison ivy: It has some lookalikes. You’ve probably heard the old saying, “Leaves of three, let it be.” That’s good advice — poison ivy doesn’t really stand out in a crowd, but it always has three leaflets on each leaf.

However, small box elder (Acer negundo) seedlings look similar, and they tend to grow in the same places you’ll find poison ivy — along the fence, behind the garage, and other places where you may not do a lot of cultivating. The clues? Boxelder stems often have a grayish “bloom” on them.

Another lookalike is Boston ivy (Parthenocissus tricuspidata), especially small, new growth. Unfortunately, it has a red stem, just like poison ivy, so it’s a little harder to tell apart. Usually the leaf edges are a little more jagged, and the leaves are slightly smaller. But when in doubt, it’s best to be careful!

Click to see a foliage detail.

problem solver

Pennsylvania pellitory
Parietaria pensylvanica

IDENTIFICATION — Growing 6 to 18 in. tall, Pennsylvania pellitory has leaves with slightly fuzzy undersides. Click the image to see a foliage detail. At first glance, this spring weed’s narrow upright form looks broader because the plant often grows in dense colonies. The green flowers along the main stems have no petals and are barely noticeable.

FAVORITE CONDITIONS — Although it prefers part shade, you’ll find Pennsylvania pellitory in full sun if the soil never dries out. It reseeds rampantly, especially in areas that are tilled annually.

CONTROL — The shallow, fibrous roots are easy to pull or hoe out. (Check out our favorite hand hoe.) If you miss pulling a few weeds, red admiral butterfly caterpillars will enjoy eating the leaves. But herbicides are effective if you need to eradicate large stands of this annual.

Read about more spring weeds in the April issue of Garden Gate magazine. On newsstands now!

Click for a foliage detail.

problem solver

Box elder
Acer negundo

IDENTIFICATION — Box elder leaves have three lobed leaflets that are somewhat pointed. The stems are smooth green to dark red with a white waxy coating that you can rub off with your fingers. Click to see a foliage detail.

A single or multi-stemmed tree that grows up to 75-ft.-tall, box elder is not good to have in your garden. Winged seeds can sprout almost anywhere and new trees can also sprout from the shallow roots, which make it hard to grow anything nearby. In addition, its weak wood breaks easily in storms.

FAVORITE CONDITIONS — Box elder is not picky. Any place in full sun to part shade with moist, even wet soil is fine. It readily adapts to almost any conditions except deep shade or very dry soil.

CONTROL — Pull seedlings if you spot them when they’re young enough. This is the best method in areas where you can’t dig or spray, such as in ground cover beds.

Spray young sprouts in open, mulched areas with nonselective herbicides, such as Roundup^® Poison Ivy & Tough Brush Killer Plus. Always follow the label directions, but you usually apply these products to actively growing weeds in spring or summer.

Digging is the preferred method in beds where spraying a herbicide would be risky for the other plants. Plus, unlike spraying actively growing weeds, digging lets you get rid of box elder any time you can push the shovel into the soil.

Once box elder gets too big to dig, you’ll need to use a saw to remove it. Then dribble or brush on a systemic stump killer around the edges where the sap is flowing. It’s absorbed into the wood and kills the roots.

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Crown vetch
Coronilla varia

IDENTIFICATION — Crown vetch grows up to 2 ft. tall. It has a dense, sprawling habit with stems that can be 5 to 6 ft. long. Pink flowers are followed by 3-in.-long seed pods. Although it’s still being sold and planted, you do not want this near your garden. It can spread quickly with seeds, root and stem pieces, and it’s tough to get rid of.

FAVORITE CONDITIONS — You’ll find this pest in full sun to part shade in rocky or rich soil. Once used to control erosion along roadways, this weed escaped and is forcing out native plants.

CONTROL — Dig crown vetch out of established gardens or use a selective herbicide in turf areas. It’s a perennial, so for the best control, apply herbicide in fall, before the leaves go dormant, and again in spring as the leaves emerge. Repeated mowing also keeps this weeds from producing seeds.

When you’re tackling crown vetch and other weeds with tough roots, a good weeding tool, such as our Soil Knife, really comes in handy.

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Stinging nettle
Urtica dioica

IDENTIFICATION — If you’ve ever walked along a wooded path, you’ve probably encountered stinging nettle. This perennial weed, with bright- to dark-green leaves, can grow to 3 to 6 ft. high. The square stems are covered with fine hairs, which break and release a sap when you brush against the plant. If the sap gets on your skin, it causes a stinging feeling that lasts for a few minutes or longer, depending on how sensitive you are. From May to October, pale green flowers open along the stem between the leaves.

FAVORITE CONDITIONS — You’ll find stinging nettle in damp, fertile, shady locations. In the wild, it grows well along stream banks and at the edge of wooded areas. But it’ll also tolerate more sunny spots, such as an open field or roadside. In the garden, stinging nettle may pop up on bare soil, too.

CONTROL — Stinging nettle spreads by seed and by rhizomes, which allow it to colonize an area quickly. To control small patches or individual plants, pull them by hand, but be sure to wear gloves and long sleeves so you don’t get “stung.” If you’re dealing with a large colony of plants, try mowing them off and using a garden fork to remove the roots. Herbicides, such as glyphosate or 2,4-D, are also effective and spraying them keeps you from coming in contact with the plant.

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Common buckthorn
Rhamnus cathartica

IDENTIFICATION — Growing quickly to a large shrub or small tree up to 20 ft. tall, common buckthorn has sharp spines at the tips of the twigs that can be dangerous as you walk through brushy areas. If you scratch the bark of this woody weed and it’s yellow underneath, you’ve found common buckthorn. Late in fall you’ll also notice that the foliage stays on this pest long after other leaves have fallen. And look closely at the leaves — there are usually three to five pairs of veins in each one.

FAVORITE CONDITIONS — Common buckthorn prefers places in part shade in moist to dry soil.

HOW IT SPREADS — Birds eat and spread the seeds of the 1/4-in.-diameter messy black fruit in fall.

CONTROL — When the plant is a seedling, pull or dig it out of the ground. If it’s too large for this, spray the plant with a nonselective herbicide, such as Roundup^® Poison Ivy & Tough Brush Killer Plus in spring or late summer. Or cut down the tree and dribble or brush on a systemic stump killer around the edges where the sap is flowing. It’s absorbed into the wood and kills the roots. Be careful, it can kill any plant it gets on.

problem solver

Gooseneck loosestrife
Lysimachia clethroides

IDENTIFICATION — It may produce attractive arched white flowers in late spring to summer, but this aggressive 3-ft.-tall plant can take over your garden quickly.

FAVORITE CONDITIONS — Gooseneck loosestrife prefers part shade and moist soil. Dry soil and full sun scorch the foliage and slow down the plant’s growth. It’s cold-hardy in USDA zones 4 to 9 and heat-tolerant in AHS zones 9 to 1.

CONTROL — If you want to grow it, contain the roots in a buried plastic pot. The roots can be hard to pull, so digging any time of year is best. You can also use nonselective herbicides.

A BETTER ALTERNATIVE —Nothing else will have those distinctive arching goose necks, but bluestar will have a similar size and texture. Between 2 to 3 ft. tall with an equal spread, it’ll bloom best in full sun to part shade. The clusters of pale-blue flowers open in late spring. Bluestar (Amsonia tabernaemontana) is cold-hardy in USDA zones 3 to 9 and heat-tolerant in AHS zones 9 to 1.

problem solver

Common mullein
Verbascum thapsus

IDENTIFICATION — At first glance, this weed could be a tall, striking ornamental for the back of your border. But its soft gray foliage and tall spikes of yellow flowers can be deceiving. It could take over your garden. Just one common mullein plant is capable of producing about 180,000 seeds, which can remain viable in the soil for 100 years or more.

Common mullein, also known as woolly or flannel mullein, is a biennial. The first year it’s a low rosette of gray feltlike leaves that can be more than a foot long. In its second year of growth, cylindrical spikes of small cup-shaped yellow flowers appear. The flower stalk can be up to 8 ft. tall and often blooms from June until early October. Both the leaves and the stem are covered in soft woolly hairs. Spent flower stalks remain standing through the winter.?

FAVORITE CONDITIONS — Found throughout much of North America, common mullein prefers lean, dry sandy soils. But it will adapt and grow just fine in richer soils, too. And like many plants with gray woolly foliage, common mullein needs plenty of sun to reach its full size. Some of its favorite spots are gravelly areas like ditches, railroad embankments or along driveways. Occasionally you’ll find it growing in vacant lots, fence rows or old garden areas that are rarely cultivated.

CONTROL — You can easily pull common mullein plants out by hand, especially in loose or gravelly soil, because they usually have a single taproot. But if you can’t pull a mature plant, make sure to remove any blooms and seed capsules before they spread. To prevent any unwanted seedlings, dispose of the removed stalks in plastic bags that you send away in the trash.

Herbicides are especially effective on young plants. Apply glyphosate, a nonselective herbicide, to the foliage while the plant is actively growing in spring.

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Chicory
Cichorium intybus

IDENTIFICATION — The line between wildflower and weed can be narrow. With chicory, or blue sailor weed as it’s sometimes called, what one person considers a lovely blue flower, a neighbor might consider a weed. This is one of those perennials that can go either way.

In summer, branched flower stems spring up from the center of a low rosette of leaves that looks very much like a dandelion. These tough stems can reach more than 7 ft. tall, but the average is usually less than 3 ft. The leaves along the tough stems are small and not very noticeable. Underground there’s a fleshy taproot that if broken, will “bleed” a milky white sap. But the daisylike flowers (usually blue, but sometimes pink or white) are what you’ll notice first.

Each morning the flowers open facing the rising sun. They last just one day, so by late afternoon they fade and wither. But rest assured there will be more tomorrow morning.

You can eat tender young chicory leaves in salads or as a cooked green. Roots are cooked and eaten or dried and ground to make a coffee substitute.

FAVORITE CONDITIONS — This European native has naturalized across much of North America. You’ll spot it growing along roadsides or the edge of your garden. It does not like areas that are frequently cultivated or mowed to less than 2 in. tall.

CONTROL — Just like a dandelion, chicory spreads mainly by seeds, so you’ll want to keep it from setting seeds. However, pieces of root will also grow quite easily. Repeatedly mowing the plant short, or cutting it off at the soil line will eventually kill it. The taproot is hard to pull from the ground, even after soaking the area with water first. Broadleaf or non-selective herbicides are also effective at getting rid of chicory.

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Fuller’s teasel
Pastinaca sativa

IDENTIFICATION — Originally introduced from Europe for use as a dried flower, Fuller’s teasel has naturalized in much of North America. The first year, this biennial forms a rosette of oblong leaves that may grow to nearly 12 in. long. During the second year, several flower stalks with spines shoot up nearly 6 ft. The spiny egg-shaped lavender flowers bloom from June to October. After flowering and producing seed, the plant dies.

FAVORITE CONDITIONS — Fuller’s teasel prefers open, sunny sites like roadsides and disturbed areas, although it may grow in your lawn or garden. It’s a particular pest for restored prairies and wildlife areas because each plant is capable of producing more than 2,000 seeds and most of them will germinate. Under favorable growing conditions, it can actually outcompete native prairie plants.

CONTROL — As with all biennial weeds, it’s easier to manage Fuller’s teasel in the rosette stage. Use a dandelion-puller to pull out the long tap root or slice it off, below the soil, with a sharp spade. And as with dandelions, be sure to get as much of the root as possible so it won’t resprout. You can cut off the flower head to prevent it from going to seed. Herbicides that contain triclopyr or glyphosate can also be used, but are most effective when applied while the plants are in the rosette stage before they flower.