Plant spikerush at the waterline, in wet mud or a pond basket, and keep the mix saturated from day one.
Plant at the waterline, in wet mud or a pond basket
| Factor | Recommended | Avoid |
|---|---|---|
| When | Into a wet shelf, bog, or pond margin that will not dry | Do not set plugs into a border that dries between storms |
| Set | Crown at the waterline, at the same depth it grew in the pot | Do not perch the crown high and dry, or bury it in stagnant mud |
| Water over the crown | Needle: waterline to about six inches under. Pale: no more than a few inches of standing water the first year | Do not stand deep water over a new pale clump before the rhizomes run |
| Spacing | Needle plugs about six inches apart. Pale clumps about twelve to eighteen inches | Do not jam plugs into a trough with no room to mat |
| Basket | Heavy loam or clay in a mesh basket, with a thin gravel cap if you need to contain the shelf | Do not use a light potting mix that floats, then dries |
Set the crown at the waterline, at the same depth it grew in the pot. A pond basket of heavy loam or clay stays put; light potting mix floats and then dries. [1] needle spikerush can sit at the waterline or as much as six inches under. pale spikerush wants a permanent wet edge and a shallow first year so the rhizomes can run. [2]
How deep do I plant it?
Set the crown at the waterline, at the same depth it grew in the pot. Needle spikerush can sit as much as six inches under. A dry hanging-basket mix is not the home.
How to plant spikerush
Work one plug at a time: wet site, crown at the waterline, then water to settle.
- Choose wet mud, a bog, or a pond shelf that will not dry. Needle and pale plants take the same moisture rule at different heights. [3]
- Set the crown at the waterline. Needle spikerush can sit as much as six inches under. In a mesh basket, use heavy loam or clay, not a light mix that floats. [4]
- Keep the mix saturated. The first year, stand no more than a few inches of water over a new pale clump so the rhizomes can run.
- Space needle plugs about six inches apart so they can mat. Space pale clumps about twelve to eighteen inches apart so the colony can fill.
- Water once to settle. After planting, sun and never-dry ground are on How to Grow Spikerush.
When do I plant spikerush?
Plant into wet ground that will not dry. Wait if the shelf is still frozen or will bake dry before the roots take.
Split a clump in spring
Dividing a clump uses the same planting steps. Wait until new shoots show, then cut so each piece keeps rhizome and a few stems.
- Lift a crowded clump in spring, when new growth shows.
- Split pieces that each keep roots and several green shoots. Discard soft, rotting pieces.
- Replant each piece the same day at the waterline, and keep the mix saturated while it takes.
Can I divide a clump?
Yes. Split a rhizome clump in spring and replant the pieces into wet mud at the waterline. Keep them wet while they take.
What fails at planting
Planting into a mix that dries, or standing deep water over a new pale clump, is the usual reason a start never takes. Keep the crown at the waterline. Do not use a light hanging-basket mix that floats.
If a new clump never takes, the crown sat dry or the first-year water was too deep — reset at the waterline and keep the mix saturated.
FAQ
Can I grow spikerush from seed?
Plugs and divided clumps are the sure start. Seed is slow and needs light on a wet surface. Buy a plug or split what you already have.
Related guides
Recommended plants
References
- [1] Wetland Plants Inc -
https://www.wetlandplantsinc.com/species/Eleocharis-acicularis-Needle-Spikerush - [2] Idaho Plant Materials -
https://plants.usda.gov/DocumentLibrary/plantguide/pdf/pg_elpa3.pdf - [3] Illinois Wildflowers -
https://www.illinoiswildflowers.info/grasses/plants/needle_sprush.html - [4] Pond Informer -
https://pondinformer.com/needle-spikerush-eleocharis-acicularis/
This note is part of Eleocharis Guides.
More planting notes by plant are gathered in Planting Guides.
Updated: Reviewed by Bosquelle Editors