How to Grow Rubenza
Cosmos bipinnatus
Your complete guide to growing Rubenza.
📷 Wikimedia CommonsWhen to Plant Rubenza
Planting windows vary by USDA hardiness zone. Look up yours by ZIP code.
| Zone | Start Indoors | Direct Sow | Harvest |
|---|---|---|---|
| Zone 1 | May – June | July – September | — |
| Zone 2 | April – May | June – August | — |
| Zone 3 | April – May | June – August | — |
| Zone 4 | March – April | June – July | — |
| Zone 5 | March – April | May – July | — |
| Zone 6 | March – April | May – July | — |
| Zone 7 | February – March | April – June | — |
| Zone 8 | February – March | April – June | — |
| Zone 9 | January – February | March – May | — |
| Zone 10 | January | February – April | — |
| Zone 11 | January | January – March | — |
| Zone 12 | January | January – March | — |
| Zone 13 | January | January – March | — |
Companion Plants for Rubenza
✓ Good companions
Attracts beneficial predatory insects like lacewings and parasitic wasps
Deters ants, aphids, and flea beetles while attracting bees
Attract beneficial insects and provide complementary colors in flower beds
Repels moths, fleas, and mosquitoes while attracting pollinators
Repel aphids, whiteflies, and nematodes while attracting beneficial insects
Act as trap crops for aphids and cucumber beetles, drawing pests away
Attracts beneficial insects like hoverflies and parasitic wasps
Attract butterflies and beneficial predators while providing continuous blooms
✗ Keep away from
Produces juglone toxin that inhibits growth and can kill sensitive flowering plants
Releases allelopathic compounds that suppress growth of nearby plants
Can shade out smaller flowers and release growth-inhibiting chemicals
