Generally, parsnip seeds don’t keep well; one of the most important factors in choosing the best seeds is to be sure that they are fresh. You should also consider other variables, such as the different varieties of parsnips that are available, based on both taste and appearance. Seed handling can also be a factor for some people, and you may want to consider whether or not to purchase pelleted parsnip seeds.
Since parsnip seeds have a very limited lifespan, it is important to get fresh seeds every year. Seeds that have been stored over the winter or which are more than a year old are not likely to germinate. Using them means that you will end up wasting a lot of time and effort and get very few, if any, parsnips. Starting with fresh seeds helps to avoid this problem and gives you a much better chance of having most of your seeds grow into plants.
Parsnip seeds are usually planted in the late winter or very early spring. You should wait until the ground is dry enough that the soil can be crumbled rather than trying to plant while the ground is too wet and muddy. If you find the seeds are too tiny and are difficult to hold onto, get pelleted seeds, which are available for some of the different kinds of parsnips. Pelleted seeds have a coating on them that encases each seed, making them bigger than plain seed and much easier to handle. The coating will dissolve once the seeds are planted and exposed to enough moisture.
When choosing the best parsnip seeds, look for those that will produce the type of parsnips you like. Some of these vegetables are long and narrow, like carrots, while others are more rounded or are wedge shaped. Flavors also vary from fairly bland to extremely sweet. If you aren’t sure which type of parsnip seeds will give you what you like, it is usually best to plant several different types and make a note of which ones you prefer.
When harvesting parsnips it is generally best to leave them in the ground until after the weather has been very cold for several weeks. This causes the natural starch in the parsnips to change into sugars, making these root vegetables much sweeter to eat. They can be left in the ground over the winter, if the tops are protected, but older parsnips tend to get tough and stringy. These root vegetables are best eaten when young and tender.