8 Best Companion Plants for Roses: Repel Aphids, Attract Pollinators, and Where to Buy Each
Plant these 8 companions next to your roses and watch aphid pressure drop—with peer-reviewed proof for each pick and a sourcing guide for every plant.
Most gardeners plant roses in isolation—then wonder why the aphids return every spring, why the woody bare stems look stark, and why the rose bed demands constant intervention. The fix often isn’t more spray. It’s the right neighbor.
Companion planting works on multiple levels with roses: the right plants deter pests chemically, attract the insects that eat those pests, cover bare canes aesthetically, and in some cases suppress soil-borne disease. This guide covers the 8 best companion plants for roses, explains exactly why each works, and tells you where to buy them and what to expect to pay—a buying-guide dimension no other resource covers. If you’re new to rose care, the Rose Care Guide covers pruning, fertilizing, and seasonal timing that all integrate with companion planting schedules.
Why Companion Planting Works—The Science
A 2018 peer-reviewed paper in Insects identified three distinct mechanisms by which companion plants reduce aphid pressure on host plants [1]:
- Volatile masking: Aromatic plants emit compounds that physically interfere with aphids’ host-location ability. Aphids identify target plants via chemical signals; companion volatiles mask those signals. Garlic’s sulfur-based compounds—94% of its aromatic output—are among the most potent masking agents studied. Rosemary’s α-pinene and 1,8-cineole were shown to “disturb the behavioral response of aphids” in controlled conditions.
- Predator enhancement: Flowering companions provide pollen and nectar that sustain populations of hoverflies, parasitic wasps, and ladybugs. The adults feed on flowers; their larvae eat aphids. This is a two-stage biological control loop—plant the right flowers and you’re farming your own pest-control workforce.
- Direct intercropping effect: Tagetes patula (French marigold) specifically reduced populations of Macrosiphum rosivorum—the rose aphid—in controlled intercropping trials [1].
Honest caveat: the same paper concludes that companion planting achieves only partial pest control and works best alongside resistant rose varieties and sound cultural practices. Use it as part of a system, not a substitute for one.
Seasonal Garden Calendar
Know exactly what to plant, prune and sow — every month of the year.
Top 5 Companion Plants at a Glance
| Companion Plant | Best For | Approx. Price |
|---|---|---|
| Lavender | Aphid deterrence, fragrance, deer resistance | $10–$22 (1-gal pot) |
| Catmint ‘Walker’s Low’ | Covering bare canes, continuous bloom | $8–$20 (1-qt/gal) |
| French Marigold | Peer-reviewed aphid + nematode control | $3–$10 (4-pack or seeds) |
| Ornamental Allium | Spring color + sulfur pest masking | $8–$15 (3-bulb pack) |
| Sweet Alyssum | Attracting predatory insects on a budget | $4–$12 (4-pack) |
The 8 Best Companion Plants for Roses
1. Lavender
Lavender is the most versatile companion for roses and the most broadly supported across multiple evidence tiers. Lavandula latifolia volatiles—specifically linalool and linalool acetate—reduced aphid nymph numbers in greenhouse trials [1]. Beyond aphids, lavender attracts bees that cross-pollinate roses, deters deer and rabbits with its strong scent, and acts as a groundcover to suppress weeds around rose bases.
One critical note most articles skip: lavender and roses have fundamentally different water needs. Lavender prefers lean, dry, well-drained soil; roses are heavy feeders and drinkers. Plant lavender at least 24–36 inches from the rose crown so their root zones don’t directly compete. Lavender sitting inside the regular watering zone of a rose will develop root rot over time, even if it looks healthy at first.
Best zones: 5–9 (English lavender L. angustifolia); 7–10 for Spanish/French types
Where to buy: Available at most garden centers spring through fall. Online, Proven Winners and similar retailers carry 1-gallon pots for $10–$22. Look for compact, multi-stemmed plants already showing color—not pale, leggy stock from the back of the shelf.
2. Catmint (Nepeta ‘Walker’s Low’)
Catmint is David Austin’s top recommendation for the front edge of rose beds [4], and it earns the placement. Its low mound of blue-purple flower spires covers the woody bare canes at a rose’s base—the aesthetic problem most rosebeds share—while blooming simultaneously with the first rose flush. The strong fragrance deters Japanese beetles and rabbits, and the flowers attract bees for pollination.
‘Walker’s Low’ (zones 3–8) is the go-to selection: it stays under 24 inches, doesn’t flop, and reblooms from May to frost if you shear it back after the first flush. Unlike true mint, catmint is not invasive—it spreads slowly and stays where planted.
Where to buy: Widely available in spring at local garden centers and big-box stores. Proven Winners and High Country Gardens carry it online for $10–$20. It also divides easily from an established clump, making it nearly free after the first purchase.
3. French Marigold (Tagetes patula)
French marigold is the only companion plant on this list with direct peer-reviewed evidence specifically against the rose aphid (Macrosiphum rosivorum) in intercropping trials [1]. The mechanism is dual: adult hoverflies are attracted to the flowers and their larvae eat aphids; marigold root exudates also suppress root-knot nematodes in the soil. This makes it the best pick when you’re dealing with both above-ground aphid pressure and below-ground nematode problems simultaneously.
Use French marigold (T. patula—bushy, 8–12 inches), not African marigold (T. erecta), which grows too tall and dense to tuck neatly around rose bases.
Zones: 2–11 annual
Where to buy: The most affordable pick on this list. 4-packs cost $3–$8 at garden centers; seed packets start around $2. Direct-sow after last frost, or start indoors 4–6 weeks early for earlier aphid-season coverage.
4. Garlic and Ornamental Alliums
Garlic carries the strongest documented evidence of any herb companion. Its volatile compounds—94% sulfur-based—mask the chemical signals aphids use to locate host plants. In field trials, garlic intercropping “delayed the appearance of winged green peach aphids and decreased abundance during peak periods” [1]. Many gardeners also report inhibition of black spot (Diplocarpon rosae) and powdery mildew, and deterrence of Japanese beetles and cane borers—though these claims are largely observational and not yet peer-reviewed.
Plant garlic cloves in October–November around the drip line of your roses. They emerge in spring timed precisely to when aphid populations begin building. Ornamental alliums (Allium ‘Purple Sensation’, ‘Globemaster’, ‘Gladiator’) deliver the same sulfur-based pest chemistry with dramatically showy spherical blooms before roses open in late spring.
Where to buy: Seed garlic: garden centers and seed companies sell certified planting stock for $8–$15/lb. Ornamental alliums: order bulbs in fall from Brent & Becky’s Bulbs, White Flower Farm, or Dutch Gardens ($8–$15 for 3-bulb packs).
5. Sweet Alyssum (Lobularia maritima)
Alyssum’s honey-scented flowers attract adult hoverflies and parasitic wasps—the same insects whose larvae eat aphids. Think of it as a feeding station that keeps your pest-control workforce present and ready. A peer-reviewed review of companion plants specifically lists alyssum as a confirmed predator-attracting companion in field trials [1].
It grows 3–6 inches tall and spreads into a low carpet of white or purple blooms, making it ideal as a ground-level filler between rose crowns. It self-seeds reliably, so one investment covers future seasons. In hot-summer climates it goes briefly dormant and rebounds in fall; in mild zones it blooms almost year-round.
Zones: 2–11 annual
Where to buy: 4-packs at garden centers run $4–$8; seeds cost $2–$5. This is the best-value pest-control companion on this list.
6. Yarrow (Achillea millefolium)
Yarrow’s flat-topped flower clusters function as landing platforms for ladybugs, lacewings, and parasitic wasps. Unlike volatile-masking companions, yarrow works through predator banking—keeping aphid-eating insects present between pest events so they’re already in position when populations start building [2]. It’s drought tolerant, spreads slowly by rhizome, and comes in colors from white to deep coral red.
One caution: in the rich, fertilized beds roses require, yarrow can spread more aggressively than in lean soil. Divide clumps every 2–3 years to keep it in check.
Zones: 3–9 perennial
Where to buy: Local garden centers stock it spring through early summer for $8–$15/plant. Very easy to grow from seed, or divide from an established clump for free.
7. Lady’s Mantle (Alchemilla mollis)
Lady’s mantle solves the bare-canes problem from a different angle than catmint. Its scalloped, velvety leaves collect morning dew in perfect silver beads and spread into a ground-level mound that hides the woody lower stems of climbing and shrub roses. The chartreuse flower sprays in early summer bridge the gap before roses fully open, and the dense foliage suppresses weeds and retains soil moisture through summer heat.
It’s a better choice than catmint for shaded edges or partially shaded beds—it tolerates more morning shade while still performing well. It doesn’t repel pests through volatile chemistry, but contributes to the garden ecosystem by attracting small beneficial insects [2].
Zones: 3–7
Where to buy: Less common at big-box stores. Look at specialty perennial nurseries, or order from White Flower Farm or Bluestone Perennials ($10–$16/plant).
8. Parsley (Petroselinum crispum)
Parsley is underrated as a rose companion—cheap, edible, and biennial in a way that generates two different benefits across two years. In year one it’s a compact deterrent: its aromatic foliage repels aphids and rose beetles [5]. In year two, when allowed to bolt, it produces umbel flowers that attract parasitic wasps, converting into a predator-enhancement companion. Plant it at ground level in gaps between rose crowns where it won’t compete for light.
Replace it annually if you want continuous year-one deterrent coverage, or let some plants bolt in year two for the predator-attracting benefit.
Zones: 2–11 biennial
Where to buy: Transplants at any garden center or grocery store cost $2–$4/plant. Grows easily from seed started indoors in late winter.
What Not to Plant Near Roses
Fennel (Foeniculum vulgare): Skip it. Fennel is allelopathic—it releases root compounds that suppress the growth of many nearby plants. Despite appearing on some companion planting lists, no authoritative horticultural source endorses it as a rose companion, and the allelopathy risk is real and documented.
Mint (Mentha spp.): The aromatic foliage does deter some pests, but mint’s root system is aggressively invasive and will colonize the root zone of nearby roses within a single growing season. Containing it in a buried pot largely defeats the companion planting benefit.
Dense shade plants—bunchberry, toad lilies, leopard plant, fuchsia: All require full shade and consistent high moisture—the exact opposite of what roses need [2]. Placing them near roses guarantees underperformance for one or both plants.
Anything within 12 inches of the crown: This is the minimum spacing UC ANR establishes for all rose companions [3]. Closer than that, you impede the air circulation roses require to prevent black spot and powdery mildew—the two most common and damaging rose diseases.
Spacing and Planting Timing
The universal rule: keep every companion at least 12 inches from the rose crown. For lavender specifically, extend that to 24–36 inches because of divergent water needs. Lavender planted inside a rose’s irrigation zone will develop root rot over time.
Timing by plant type:
- Fall (October–November): Garlic cloves and ornamental allium bulbs. Cold stratification is required, and fall planting times emergence in spring precisely when aphid season starts—this timing is not optional.
- After last frost (spring): Catmint, marigolds, alyssum, yarrow, parsley transplants. All can go in at the same time your roses are pruned and pushing new growth.
- Lavender and lady’s mantle: Spring planting preferred; established 1-gallon plants settle in faster than small plugs when planting alongside young roses.
David Austin Roses recommends trialing companions in pots for a season before committing to in-ground placement [4]—practical advice when you’re uncertain about mature-size spacing. For a full overview of companion planting principles beyond roses, the Companion Planting Guide covers vegetable-to-vegetable pairing and intercropping strategies.
Where to Buy Rose Companion Plants
Online specialty nurseries offer the widest variety selection and generally larger, healthier plants:
- Proven Winners: catmint, lavender, alyssum—reliably labeled varieties at $12–$20/plant
- High Country Gardens: drought-tolerant selections; good for western US gardeners—catmint, yarrow, lavender
- Brent & Becky’s Bulbs: ornamental alliums and garlic, fall ordering window (August–October)
- White Flower Farm: lady’s mantle, alliums, premium perennial selections
- Bluestone Perennials: good value on lady’s mantle and yarrow in smaller plug sizes
Local garden centers are best for checking plant health before purchase. Look for 1-gallon pots with multiple stems and no yellowing. Avoid leggy 4-inch seedlings of perennials—they take far longer to establish and fill gaps. Marigolds, alyssum, and parsley are fine to buy as 4-packs from big-box stores.
Buying format guide: Ornamental alliums must be ordered as bulbs in fall. All annuals (marigold, alyssum, parsley) are cheapest direct-sown from seed. Perennials—lavender, catmint, yarrow, lady’s mantle—are worth paying for established plants if you need coverage this season, as they can take a full year to reach useful size from seed or small plug.
Frequently Asked Questions
What is the single best companion plant for roses to deter aphids?
Garlic has the strongest peer-reviewed evidence—its sulfur-based volatiles are the most documented aphid-masking compounds in controlled field trials. For immediate coverage, combine fall-planted garlic bulbs with a border of sweet alyssum to sustain predatory insects through the season.
Can I grow marigolds with roses?
Yes—French marigold (Tagetes patula) specifically. It’s the variety with direct evidence against the rose aphid in intercropping trials. Plant after last frost in the gaps between rose bushes. Avoid African marigold (T. erecta)—too large and dense for this purpose.
How close can companion plants be to rose bushes?
Minimum 12 inches from the rose crown per UC ANR guidance [3]. For lavender, extend that to 24–36 inches due to its dry-soil preference. Closer companions reduce air circulation and promote fungal disease.
Sources
- “Companion Plants for Aphid Pest Management” — Insects, 2018. PubMed Central.
- “Companion Planting for Roses” — New York Botanical Garden Library Research Guide.
- “Best Friends in the Garden: Companion Planting” — University of California ANR Blog.
- “Companion Planting” — David Austin Roses.
- “Companion Plants for Roses” — Blooming Backyard.
