Verbena seeds are tiny, elongated, stick-like structures that are easy to overlook and even easier to mistake for bits of dried plant debris. Depending on the species, individual seeds typically measure just a few millimeters long and are narrow enough that dozens can sit on a fingertip. Their small size and dull coloring are the main reasons gardeners struggle to identify them, collect them, or even spot them in a seed packet.
Size, Shape, and Color
Across the Verbenaceae family, seeds range from roughly 1 to 5 mm in width and about 1.8 to 6.4 mm in length, though the most commonly grown garden verbena species tend to sit on the smaller end of that range.1PubMed. Implication of scanning electron microscopy and light microscopy for oil content determination and seed morphology of Verbenaceae Most verbena seeds you will encounter are roughly 2 to 3 mm long, making them comparable in size to a grain of coarse sand or a flake of cracked pepper. They are distinctly elongated rather than round, with a slim, slightly curved profile that tapers at one or both ends.
Color ranges from pale tan to medium brown to nearly black, depending on the species and how mature the seed was at harvest. Freshly harvested seeds tend to be lighter, while fully dried seeds darken over time. The surface is not smooth. Under close inspection you can see fine ridges running lengthwise along the seed, giving it a subtly striated or grooved texture. This ridging is one of the most reliable visual cues that you are looking at a verbena seed rather than a random speck of organic matter. Texture, color, and surface patterning all vary meaningfully between species within the family.1PubMed. Implication of scanning electron microscopy and light microscopy for oil content determination and seed morphology of Verbenaceae
Why They Are Technically Nutlets, Not Seeds
What gardeners call a “verbena seed” is, in strict botanical terms, a nutlet. Verbena flowers produce a small, dry fruit that splits at maturity into four individual nutlets, each containing a single seed inside a thin but hard outer wall. The distinction matters for practical purposes because that outer wall is part of why verbena can be slow and finicky to germinate. You are not planting a naked seed directly into soil; you are planting a seed enclosed in a protective shell that moisture must penetrate before anything starts growing.
The nutlets cling together inside a papery calyx (the dried remnants of the flower’s base) until they are shaken loose by wind, rain, or your fingers. When you shake a dried verbena flower spike over a piece of paper, the tiny nutlets that fall out are the “seeds” you plant. Each one looks like a slender splinter of wood, slightly flattened on one side and rounded on the other. That flat-and-round cross section is another helpful identification feature.
Where to Find Seeds on the Plant
Verbena flowers bloom along upright spikes, and the seeds develop in sequence from the bottom of the spike upward. The lowest flowers on a spike are the first to be pollinated, the first to fade, and the first to set seed. By the time the top of the spike is still showing fresh color, the bottom may already contain ripe nutlets tucked inside dried-out calyxes.
This staggered ripening is why collecting verbena seeds can be frustrating. If you wait until the entire spike looks brown and spent, the earliest seeds may have already dropped to the ground. If you harvest the spike while the top is still blooming, the upper seeds will not be mature. The practical workaround most gardeners use is to slip a small paper bag or envelope over a nearly finished flower spike and secure it loosely. As seeds ripen and fall, they drop into the bag instead of onto the ground. You can also cut whole spikes once the lower two-thirds have turned brown and dry them upside down over a sheet of paper indoors.
When you crush or roll a dried section of spike between your fingers, you will feel the tiny nutlets separating from the chaff. The chaff is the dried calyx material, stems, and other flower parts. Verbena seeds and chaff look frustratingly similar at first glance because both are small, brown, and dry. Separating them by hand requires patience and good lighting. A fine mesh sieve or a gentle breeze across a paper plate helps sort the heavier nutlets from the lighter chaff.
Differences Between Common Verbena Species
Not all verbena seeds look the same, and the species you are growing affects what you should expect. The genus Verbena contains more than 250 species, and numerous hybrid cultivars exist in the garden trade. A few of the most widely grown types illustrate the range of seed appearances.
- Verbena bonariensis: One of the tallest garden verbenas, with airy purple flower clusters on long stems. Its seeds are among the smallest in the genus, barely 2 mm long, dark brown, and very narrow. They look almost like tiny dark slivers.
- Verbena hastata (blue vervain): A North American native wildflower. Seeds are slightly broader and more robust, medium brown, and a little easier to handle than those of V. bonariensis.
- Verbena rigida: Produces somewhat larger nutlets with a more pronounced ridged texture on the surface. Easier to spot and collect by hand.
- Hybrid garden verbenas (V. × hybrida): The trailing, colorful verbenas sold in nursery packs. Seeds are small and brown, and germination rates from home-saved seed are often poor because many hybrids do not breed true or produce viable seed reliably.
If you have purchased a seed packet labeled simply “verbena” or “verbena mix,” the seeds inside are usually from hybrid cultivars or from V. bonariensis. Open the packet over a white surface in good light. You should see small brown or tan elongated specks, possibly mixed with a small amount of chaff or inert filler. Seed companies sometimes add inert material so the tiny seeds distribute more evenly during sowing.
Telling Viable Seeds from Duds
Because verbena seeds are so small and nondescript, it is hard to judge viability by appearance alone. However, a few visual and tactile cues help. Plump, firm nutlets with consistent brown coloring are the most likely to germinate. Seeds that look shriveled, hollow, or papery when you pinch them gently between your fingernails are often empty, meaning the nutlet formed but no mature seed developed inside. Pale or greenish seeds were harvested too early and are unlikely to sprout.
A simple float test gives a rough indication. Drop seeds into a glass of room-temperature water and wait ten minutes. Seeds that sink tend to contain a solid embryo and endosperm. Seeds that float are often hollow or immature. This method is not perfectly reliable for seeds this small, since surface tension can keep even viable seeds floating, but it is a useful first pass if you have a batch of unknown quality.
Verbena seed viability drops noticeably with age. Fresh seed harvested in the current season and stored in a cool, dry place will give far better germination than packets that have been sitting in a warm garage for two or three years. If you are saving your own seed, label envelopes with the harvest date and use them within a year or two for best results.
Why Verbena Seeds Are Hard to Germinate
Even when your seeds are viable and fresh-looking, verbena has a reputation for uneven and slow germination that catches new growers off guard. Several factors contribute, and most of them trace back to the seed’s physical structure.
The nutlet’s hard outer wall creates a natural barrier to water absorption. Until moisture reaches the embryo inside, germination cannot begin. Some growers soak seeds overnight or wrap them in a damp paper towel for 24 hours before sowing to give moisture a head start. Others nick the seed coat lightly with fine sandpaper, a technique called scarification, to create tiny openings that let water in more quickly.
Many verbena species also benefit from a period of cold stratification, which mimics the winter chill that seeds would experience outdoors in their native range. Placing seeds in a sealed bag with slightly damp sand in the refrigerator for two to four weeks before sowing can improve germination rates substantially. This is especially helpful for native species and less necessary for modern hybrid cultivars, which have often been bred for easier germination.
Light is another variable. Verbena seeds generally germinate better in darkness. When sowing indoors, covering seed trays with a thin layer of vermiculite or a sheet of newspaper keeps light out while still allowing air exchange. Germination typically takes anywhere from 14 to 28 days at soil temperatures around 65 to 75°F (18 to 24°C), though stragglers can appear weeks later.
Confusing Verbena With Lantana and Other Relatives
Because verbena and lantana both belong to the Verbenaceae family, their seeds share some structural similarities, and gardeners occasionally mix them up. Lantana seeds are encased in a fleshy berry that turns dark purple or black when ripe. If you clean away the berry pulp, the hard seed inside is roughly round and about 3 to 4 mm across, a different profile than verbena’s slim, elongated nutlets. If you find round, hard, pellet-like seeds from a plant you thought was verbena, you are probably looking at lantana.
Lemon verbena (Aloysia citrodora) is another source of confusion. Despite sharing the “verbena” name, lemon verbena is a different genus entirely. It rarely sets viable seed in cultivation, and when it does, the seeds are tiny and enclosed in structures that look somewhat different from true Verbena nutlets. If you are trying to grow lemon verbena from seed, you are in for a difficult time; propagation by cuttings is far more reliable for that plant.
Buying Seeds Versus Saving Your Own
When you order verbena seeds from a reputable seed company, the packet usually contains cleaned, sorted seeds with chaff removed. They may be treated with a fungicide (often visible as a colored coating, making the seeds look pinkish or bluish rather than their natural brown). Untreated organic seed will look like the plain brown nutlets described above.
Saving seed from your own garden is straightforward for open-pollinated species but less rewarding for hybrids. Open-pollinated verbenas (V. bonariensis and V. hastata are two popular examples) produce seeds that grow into plants resembling the parent. Hybrid garden verbenas bred for specific colors or trailing habits often produce seed that either will not germinate or grows into plants with different characteristics than the parent. If you invested in a specific hybrid variety for its exact flower color, you are better off buying fresh seed or new plants the following year rather than relying on saved seed.
When saving seed yourself, the resulting batch will always contain more chaff and empty nutlets than a commercial packet. Expect lower germination rates and sow more heavily to compensate. Spread your harvest on a white plate, remove obvious stem fragments and chaff, and store the cleaned seeds in a labeled paper envelope inside a jar with a small packet of silica gel desiccant to absorb excess moisture. Keep the jar in a cool, dark spot.
Pelleted and Coated Seed Options
Because raw verbena seeds are so tiny and awkward to handle, some seed companies sell pelleted versions. Pelleted seeds are individual seeds coated with a layer of clay or inert material that makes them larger, rounder, and easier to pick up and space evenly. A pelleted verbena seed might be 2 to 3 mm in diameter and roughly spherical, looking nothing like the natural nutlet inside it. The pellet is usually white or light gray and dissolves after watering, releasing the seed beneath.
Pelleted seeds are popular for commercial growers who use mechanical seeders, but they are also handy for home gardeners who struggle to handle individual nutlets. The trade-off is that pelleted seed has a shorter shelf life than raw seed because the clay coating can absorb ambient moisture over time, potentially triggering premature germination or fungal problems in storage. Use pelleted seed within the season you buy it.
If you open a packet expecting tiny brown slivers and instead find uniform white balls, you have pelleted seed. Both forms are planted the same way; the pellet just needs to be kept consistently moist after sowing so the coating breaks down and the seed inside can absorb water. Letting pelleted seeds dry out after initial watering can cause the clay to re-harden around the seed, making germination even more difficult than it would have been with raw seed.
Quick Visual Identification Checklist
When you have a handful of tiny brown specks and you are not sure whether they are verbena seeds or garden debris, run through these checks:
- Shape: Elongated and narrow, not round. Slightly curved, with one flat side and one rounded side.
- Size: Roughly 2 to 4 mm long for most garden species. Small enough that you need good light to see detail.
- Color: Tan, medium brown, or dark brown. Not black, not green, not red.
- Texture: Fine lengthwise ridges visible under magnification or in strong side-lighting. Not perfectly smooth.
- Hardness: Firm when pressed between fingernails. A viable nutlet resists gentle pressure; an empty one crushes easily.
If the objects match all five traits, you almost certainly have verbena seeds. A cheap magnifying glass or the macro mode on a phone camera makes the surface ridging much easier to see and can settle any remaining doubt.