Growing and propagating Lotus

Lotus (Nelumbo nucifera or Nelumbo lutea) are among the most rewarding aquatic plants to grow from seed. With a little patience and the right conditions, you can go from seed to bloom in a single season.

Understanding lotus seeds

Lotus seeds are remarkably durable. They have one of the longest known seed viabilities in the plant kingdom, with viable seeds documented at over 1,000 years old. The seed coat is extremely hard and impermeable, which is why scarification is essential before germination.

Step 1: Scarification

The hard outer shell must be broken to allow water absorption.

• Use a metal file, nail file, or sandpaper to abrade one end of the seed (the rounded end, opposite the pointed tip)
• File until you see a slight cream or white color beneath the dark outer coat
• Do not file too deeply or damage the embryo inside
• Alternatively, use a sharp knife to carefully nick the seed coat

This step is non-negotiable. Unscarified seeds will not germinate reliably.

Step 2: Soaking and germination

• Place scarified seeds in a clear glass or jar filled with warm water (75 to 85°F is ideal)
• Set in a warm, sunny windowsill or under a grow light
• Change the water daily to prevent bacterial growth
• Within 3 to 5 days you will see the seed swell and a small sprout emerge
• Once the sprout reaches 2 to 4 inches with a few small leaves, it is ready to pot

Do not use cold water. Lotus seeds need warmth to germinate successfully.

Step 3: Potting the seedlings

• Use a wide, shallow container with no drainage holes (lotus are aquatic)
• Fill with heavy clay soil or aquatic planting mix, avoiding peat or bark-based mixes which float
• Plant the seedling so the roots are buried but the leaves float freely at the surface
• Cover the soil with a thin layer of sand or gravel to keep it from clouding the water
• Add water slowly to a depth of 2 to 4 inches above the soil surface
• As the plant grows, gradually increase water depth

Lotus do not like being disturbed once established, so choose your container wisely from the start.

Step 4: Sun and temperature requirements

• Lotus require a minimum of 6 hours of direct sunlight daily, with 8 or more being ideal
• Water temperature should be consistently above 70°F for active growth
• In Minnesota, wait until late May or early June to move containers outdoors
• Lotus thrive in heat and will bloom most vigorously during hot summer months

Step 5: fertilizing

• Begin fertilizing only after the plant has produced several aerial (above-water) leaves
• Use aquatic fertilizer tablets pushed into the soil near the roots
• Fertilize every 3 to 4 weeks during the growing season
• Do not over-fertilize young seedlings as it can burn roots

Step 6: Blooming

• Lotus grown from seed typically bloom in their first or second year
• Flowers last 3 to 4 days and open in the morning, closing by afternoon
• After blooming, the seed pod develops and can be harvested for propagation or dried for decoration

Overwintering in Minnesota

Minnesota winters are too harsh for lotus to survive outdoors in containers.

• In late fall, after the first frost kills the foliage, cut back the stems
• Move the container to a frost-free location such as a garage, basement, or shed
• Keep the soil slightly moist but not waterlogged through winter
• Lotus tubers can survive in damp soil at temperatures just above freezing
• Return outdoors after the last frost, typically mid to late May in Minnesota

Propagation beyond seeds

Once your lotus is established, you can propagate it vegetatively.

By division

• In early spring before new growth begins, carefully divide the rhizomes
• Each division should have at least one growing tip
• Replant immediately in aquatic soil and keep warm

Saving seeds

• Allow seed pods to dry fully on the plant
• Harvest seeds when the pod turns brown and rattles
• Store in a cool, dry place in a paper envelope
• Seeds remain viable for many years if stored properly

Tips for Minnesota growers

• Start seeds indoors in April to get a head start on the short growing season
• Use dark-colored containers to absorb heat and warm the water faster
• A small submersible aquarium heater can help maintain water temperature early in the season
• Native American lotus (Nelumbo lutea) is more cold-hardy and may be a better choice for northern climates
• Dwarf varieties are well-suited to container growing and work beautifully on a deck or patio

Lotus are slow to establish but once they settle in, they are vigorous, long-lived, and absolutely spectacular in bloom.

Lotus and koi

Good news here. Lotus are non-toxic and completely safe for koi. All parts of the plant, including the leaves, stems, flowers, and seed pods, are harmless to fish. In fact, lotus are one of the most koi-friendly aquatic plants you can grow.

The more practical question is whether your koi are safe for your lotus.

Koi will absolutely eat lotus. They are notorious for nibbling on aquatic plant roots, tubers, and young growth. A hungry koi will dig around in your planting container, uproot the rhizome, and eat the tender new shoots before they ever reach the surface.

How to protect lotus in a koi pond

• Plant lotus in their own containers with a thick layer of gravel or large river stones on top, heavy enough that koi cannot easily dig through it
• Use heavy smooth stones rather than pea gravel, as koi can move small gravel easily
• Place the container in a spot where it is stable and not easily tipped
• Consider a container with a mesh or screen cover over the soil surface anchored with stones
• Raise the container on bricks or cinder blocks so it sits at the right water depth and is more stable

The benefits of lotus in a koi pond

• Lotus leaves provide shade which helps regulate water temperature and reduces algae growth
• The root system helps filter and absorb excess nutrients from fish waste
• The large floating and aerial leaves give koi some shelter and reduce stress
• They add stunning visual interest to a pond setting

Once a lotus is well established with a thick rhizome and strong growth, koi tend to leave it alone more. Young seedlings and newly planted tubers are the most vulnerable.