Should You Really Soak Seeds Before Planting? Gardening Experts Say It Depends

https://www.thespruce.com/soaking-seeds-before-planting-11687041

" .. One way to jumpstart seeds is to rehydrate them by soaking them in warm water. But is soaking every type of seed really necessary?
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Do Seeds Need to Be Soaked Before Planting?

Not all seeds need to be soaked before planting, but some types will definitely benefit from this treatment. While all seeds have an outer shell that protects the plant embryo, it is a seed with a thick outer shell that will benefit from soaking.

"This is especially common for woody ornamental and native perennial plants," says Rebecca Sideman, professor of sustainable agriculture and food systems at the University of New Hampshire College of Life Science and Agriculture.

Softening the outer shells by soaking the seeds in water makes it easier for the dormant embryo to break through to begin growing roots and leaves.

Moisture and warmth are the two most essential elements for germination until the seedling has grown leaves through which it can absorb energy.
"Seed from some plants can have one or more types of dormancy which must be overcome by stratification (soaking) before they will germinate," says Sideman.

When to Soak Seeds

If you plan to soak seeds, wait until a day or so before you plan to plant them indoors or outdoors. The seeds should not remain in water for more than 8-12 hours.

Before you get carried away and submerge all your seeds, examine the seeds and read the planting instructions on the package. Only larger seeds with tough exterior coatings should be soaked. Tiny seeds with thin outer shells do not require soaking. Soaking tiny seeds can cause them to clump together, making them almost impossible to sow.

Best Seed Soaking Tips

 1) Use warm water. Place the seeds in a shallow bowl and cover with an inch of warm water.

 2) Keep them warm. Place the bowl in a warm, room-temperature spot away from direct sunlight.

 3)  Don't soak too long. Never soak seeds for more than 24 hours. Leaving seeds in the water too long can cause rot and kill the plant embryo.

 4)  Discard floaters. Discard any older, unviable seeds that have floated to the top of the water.

 5)  Drain the seeds. Use a fine-mesh sieve to drain the water.

 6)  Plant the seeds immediately. Since the germination process has already started, the seeds need to be placed in warm, moist soil right away. Do not allow them to dry out again.

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