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How to Germinate Lotus Flower (Nelumbo Nucifera) Seeds

Lotus (nelumbo nucifera) is one of the most iconic flowers in history, and its presence can really improve the look of ponds and fountains on your property.  But lotus seeds have an extremely thick seed coat that will keep water out unless you give it some help.  The act of wearing down the seed coat to facilitate germination is called scarification.  In the case of the lotus seed, the scarification must be rather intense.  This impermeable barrier allows the lotus seed to remain viable for years, but it means a little extra work for the grower. This guide will show you just what to do and how far to scarify your seeds to give them the best chance of success.

While you can scarify many seeds on sandpaper and with other abrasive materials, it is best to use a metal file to scarify lotus flowers seeds due to the especially hard coat.  Even with a file, scarification can take a little bit of elbow grease.  We recommend scarification on the side of the seed.  It is best to place the file on a table and press the seed into the file as you rub it back and forth so you can have gravity work with you.  By trying to hold the file and the seed, it will take a lot more effort.

You will notice that the lotus seed has essentially three layers.  There is an outer shiny layer, which ends where you see the white ring on the seed in the photo.  Then there is another dark layer that comprises most of the seed coat and which will account for most of your effort when filing. There is then a yellowish layer inside the seed, which you will see once you file through the seed coat.  As you start to file, you will see a ring form.  You want to keep going until the inner part of that ring begins to turn a light tan color as you approach the yellow inside.  The seed in the picture has just broken through the seed coat and into the yellow layer.  We usually aim to stop right before this actually breaks through because it increases the chance that an infection can take hold. But if you keep the conditions clean, it will usually not affect the seed.  With that said, you do not want to file into the yellow layer if you can help it

Now that you have filed down the hard shell, water can penetrate into the embryo to begin germination.  Your next step is to toss the seeds directly into a glass or bowl or water.  Any amount of water that will fully cover the seeds is fine.  The seeds will start to swell initially. You will continue the soak until the seeds actually sprout.  This will usually take about a week, but it can sometimes take longer, especially if you did not scarify enough.  You will notice that the water can get cloudy pretty quickly. Therefore, you will want to be sure to change the water daily to reduce the risk of infection.

When the lotus seeds finally sprout, they will split open and a stem will pop out. The lotus is unique in the sense because most seeds will sprout with a taproot emerging first. In the case of the lotus, the foliage emerges first. This stem actually contains an immature leaf that will later develop. When the stem becomes about 2-3 inches it will form an angled bend, which will then straighten out. You can plant the seed at this point or choose to wait until roots form. The roots will form out of the base of the stem. It is best to sow the sprouts directly into your pond, but you can choose to sow in 8” pots and transplant later. In the case of a fountain or a manmade pond that does not have a soil bottom you can plant the seeds in large containers that you will submerge.