Raspberry Seeds
Planting Raspberry Seeds
Using raspberry seeds is not the usual way to start growing a raspberry bush. Raspberry bushes are not difficult to grow from seed, but they do grow slowly. One reason you may want to grow the new raspberry bushes from raspberry seeds, is if you have a bush whose fruit has excellent flavor. You can use the seeds from the existing bush to establish a new one that will hopefully have similarly flavor fruit.
Raspberry seeds are not as easy to harvest from the fruit as the seeds are for some other fruit bearing plants. The seeds will need to be harvested from the bushes in mid to late August or early September. You will need to find a two or three ripe fruit from the best bush that you currently have. Place the fruit in a sieve. Raspberry seeds are very small, so make sure that the sieve has very small holes. Gently rub off all of the fruit pulp, washing the fruit and seeds as you go.
The seeds will then need to be allowed to dry thoroughly. Most experienced gardeners will recommend that you place the seeds on a paper towel or other absorbent material and place them in direct sunlight to allow them to dry. It’s important to keep the seeds very dry and cool until it’s time to plant them indoors. If you are not going to plant the seeds soon, be sure that you don’t store them in a sandwich bag, as any moisture retained by the seed will not be allowed to escape the bag. This will cause the seed to either rot or sprout. Both of those will cause your seeds to not be viable.
The seeds can be planted indoors about two to three months before the last frost of the winter. In a warm climate that doesn’t receive frosts, this can be done shortly after they’ve been allowed to dry. The seeds could also be saved for later years. When it’s time to plant your seeds, place some seed compost materials in a small pot then add the seeds. Cover them with about an inch of the compost material and press on the soil firmly to compact it. The pots then need to be placed in an area where there is no sunlight and where the air temperature will remain stable at about 65 degrees Fahrenheit. The soil should be kept slightly damp, but if the soil is allowed to be too wet, the seeds could rot.
If your timing was right, a few seedlings should appear about three to four weeks before the last frost. When the seedlings are about three inches high, separate them carefully and transplant them into small pots. When they are big enough, and after the last frost, they can be taken outside. Let the plants sit in a cold frame at first and after they have adjusted to the colder climate, you can plant them in your raspberry bed.
Using this method, it’s possible to have an entire raspberry bed which came from one or two initial plants. Raspberry bushes will generally provide sparse fruit early in the summer from old stocks. Later in the summer, new stocks will have grown and will provide much more fruit. If you are propagating your raspberry bushes from seeds in order to reproduce the flavor or appearance of other bushes in your raspberry bed, then the effort will be worth it. It does take a few years for the bush to become truly established. This is a marathon, not a sprint, but in the end it will be well worth the effort.