Plant Pond Arrowhead – Corm in a Mesh Basket

Plant pond arrowhead in a mesh basket of heavy loam, with the corm at soil level and gravel on top, then set it at the waterline to about 6 to 12 inches — never deeper than about 12 inches.

Plant the corms in spring at the waterline, no deeper than about 12 inches

These plants spread by rhizomes and corms if they root in open mud. A basket keeps the crown where you can lift it. Set the corm at soil level, then cap the soil so it does not cloud the pond. [1] [2]

How to plant pond arrowhead

Work one plant at a time: fill the basket, set the corm, then lower it into shallow water.

1. Confirm grassy, broadleaf, bulltongue, or giant on the tag. If the tag is only a shop name, match it on Types of Pond Arrowhead.
2. Keep corms and rhizomes moist and cool until you plant. Do not let them dry on a bench.
3. Line a mesh aquatic basket. Fill it with heavy loam or aquatic soil. Leave a little room at the top for gravel.
4. Set the corm just under the soil, about 10 to 12 inches from the next corm. Do not bury it so deep that new leaves cannot reach air. [3]
5. Top the soil with a layer of pea gravel so the mix stays in the basket.
6. Lower the basket so the water sits from the waterline to about 6 to 12 inches over the soil. Never cover the leaves of a transplant. [4]
7. Do not plant giant arrowhead into the open pond bottom. After planting, sun and keeping extras in the pond are on How to Grow Pond Arrowhead.

Split a moist corm into a new basket

A corm with roots can fill a second basket once you lift the clump. That is faster than seed, and it keeps the new plant in a pot you can lift.

1. Lift the basket while the plant is dormant, or while you can still see the corms in wet mud.
2. Split off a corm that already has roots. Keep it moist and cool. Do not let it dry on a bench.
3. Set that corm in a lined mesh basket of heavy loam, with gravel on top — the same set as a nursery plant.
4. Lower the new basket into shallow water so the leaves stay above the surface. Bag extra scraps in the trash. Do not toss pieces into a ditch.

What fails at planting

Open mud lets rhizomes take the whole shoreline. Light potting mix floats out and clouds the water. Sinking a new plant deeper than about 12 inches keeps leaves from reaching air. Covering the leaves of a transplant smothers the shoot. A dry corm on the bench dies before it ever reaches the pond.

If you planted into open mud or sank the basket too deep, lift the rhizomes into a shallow basket now — do not wait for a stand you cannot pull.