Shrubs 1–2.5 (–3.5) m high, the internodes 1.5–6.5 cm long. Stems densely and closely tomentose with whitish interwoven sessile to short-stalked porrect stellae, the stalks to 0.6 mm long, the rays 6–10, ca. 0.2 mm long, usually not straight, relatively weak, the midpoint slightly shorter than the rays; stems unarmed or with a few prickles to 3–9 mm long, stout, from a broad base, straight or recurved, stellate in the lower half.
Sympodial units plurifoliate, not geminate.
Leaves simple, the blades 5.5–13 (–18) × 2.5–14 (–17) cm, the entire ones ca. 2 times as long as wide, the larger and lobed ones often very broadly ovate and nearly as wide as long, initially tomentose with sessile stellae like those of the stem, soon glabrate, somewhat shiny and drying nearly black abaxially, much more densely and persistently whitish-tomentose abaxially with hairs like those of the stem, the midrib and larger veins sometimes glabrescent and appearing much darker, the blade usually unarmed or with a few straight acicular prickles to 1.2 cm long on the major veins adaxially; 3–4 principal lateral veins on each side of midvein; base acute to rounded or truncate, or somewhat cordate in the lobed leaves; margin entire or irregularly sinuate or angulate, to very deeply 2–3-lobed with the lobes again lobed, and the basal lobes spreading to somewhat recurved; apex acute to attenuate; petioles 1–2.5 (–3) cm long, whitish stellate-tomentose, unarmed or with a few straight prickles to 4 mm long.
Inflorescences 5–12 (–20) cm in flower, to 16 cm in fruit, terminal but soon overtopped and lateral, extra-axillary, 4–12-branched, with 60–150 flowers, with all flowers apparently perfect but many fewer fruits formed than flowers, the axes closely stellate-tomentose with hairs like those of the stem, unarmed; peduncle (0.7–) 1.5–3.5 cm, the branches 3.5–7 cm; pedicels 10–12 mm, spaced 1–2.5 mm apart, articulated at the base, 13–20 mm in fruit, gradually ampliate distally and strongly reflexed in fruit.
Flowers homostylous, 5-merous. Buds ovoid, densely and finely stellate-tomentose, the caudate tips of the calyx lobes with few stellae and the dark surface strongly contrasting with the white-tomentose corolla. Calyx 3–3.5 mm long, the tube 2–3 mm long, the lobes 1 × 0.8 mm, deltoid, splitting in the sinuses and in fruit oblong-lanceolate and 4.5 × 2 mm, finely white stellate-tomentose abaxially, glabrous adaxially. Corolla 2–2.8 cm in diameter, 1.4–1.6 cm long, stellate with well-developed glabrous interpetalar tissue, purple or lilac, the tube 0.7–1.1 cm long, the lobes 0.7–0.8 × 0.7–0.9 cm, triangular, the midzone ca. 9 × 2.5 mm, densely, finely and closely stellate tomentose abaxially, glabrous adaxially except for sparse weak simple hairs on the upper part of the thickened midrib. Stamens with filaments 0.9–2 mm, glabrous; anthers 5.3–7 × 0.8–1.4 mm, free, attenuate, yellow, with minute apical pores, the pores directed distally. Ovary with a few minute simple gland-tipped hairs near the tip and sometimes with a few minute, weak sessile stellae; style 7.5–10 mm long, filiform, glabrous except for a few minute simple gland-tipped hairs in the lower part; stigma capitate.
Fruits a berry, 0.9–1.7 cm in diameter, globose, the immature fruits green, turning orange or yellow, glabrous or with a few minute weak whitish stellae.
Seeds 3.4–4.0 × 2.5–3.0 mm, flattened-reniform, yellowish tan, the surface minutely pitted.
Known from a wide variety of habitats of disturbed forests, secondary growth, dunes, restingas, disturbed cerrado, rocky soils and roadsides from Rio Grande do Norte, Brazil to Mato Grosso do Sul and Rio Grande do Sul in the south; Solanum paniculatum is common in the eastern half of Paraguay and has recently been found in Corrientes, Argentina; from sea level to 1100 m.