Should you pre-sprout potatoes?

Even without pre-germination, potatoes sprout reliably and form numerous tubers. So why should the gardener take on more work? Proponents cite some benefits, but do they really exist?

The potential benefits

Horticultural practice has proven time and again that planting pre-germinated tubers has some advantages later in the cultivation process. More specifically, the following three are:

  • the new tubers are ready to harvest faster
  • the harvest quantity is larger (approx. 20%)
  • Potato diseases encounter more resistant plants
Tip: It’s worth prepping, especially with early potato varieties. The tubers are usually large enough to be harvested from mid-May, at the same time as the long-awaited asparagus season begins. This early harvest also means that Solanum tuberosum, which is the scientific name for potatoes, avoids some of the diseases that affect the nightshade family later in the garden year.

Decision for or against pregermination

The benefits outlined above are no small thing. Experts are therefore clearly in favor of driving. Especially with regard to the occurrence of possible potato diseases, which pre-germinated plants either suffer from earlier harvestingavoid them entirely or at least face them with more resilience. Nevertheless, the question of whether potatoes should be pre-germinated cannot be answered exclusively and universally with yes. After all, it also involves work. A suitable place in the house must also be found first. In addition, planting non-pregerminated tubers can also produce acceptable results. So every hobby gardener has to weigh up for himself which approach is more worthwhile for him. If he decides to advance, he should do so according to the instructions so that he can get the best out of the tubers.

The ideal time

Around 200 different potato varieties are grown in Germany, roughly divided into early, medium and late ripening varieties. Their planting time varies by a few weeks, depending on the variety it is somewhere between mid-March and the end of May. The time for pre-germination must also be based on this. Based on the planting time and the duration of the germination process, you can easily find the optimal date:

  • Early varieties can be pre-germinated from mid-February
  • other potato varieties from March
  • start about 6-8 weeks before the planned planting date
  • when germinating without soil about four weeks before planting

The optimal environment

Potatoes cannot germinate outside in the bed. It’s still too cold early in the year for that. However, any room that offers plenty of light and a constant temperature between 10 and 15 °C should be considered. Check whether the selected spot is available for germination until the planting date and that it does not get direct sun.

Viable tubers

Set aside a few smaller, undamaged tubers from last year’s harvest. This is a particularly inexpensive way to get seed bulbs for the following year. Don’t worry, they will survive the long time until spring if they are stored as follows:

  • dark
  • cool (about 4-8 °C)
  • dry
Tip: You can also use the commercially available, much cheaper ware potatoes for cultivation. However, you should only use tubers that have not been treated with a sprout inhibitor.

Suitable containers

You need a large container, or several smaller ones, where you put the potato tubers. For example, a large wooden box, light-colored plastic box, multi-pot tray, decomposable pots or egg cartons.

Instructions for priming without soil

A shallow box is ideal for the soilless approach, or two or more for larger amounts of tubers. These are the further steps:

  1. Spread the tubers out in the box without overlapping them. The tubers can be placed vertically in egg boxes or multi-pot trays.
  2. Spray the tubers with some water.
  3. Place the containers with the potatoes in the ideal germination spot.
  4. Spray the potatoes with a little water for a few more days.
  5. Regularly sort out any rotting tubers.

With this method without soil, the duration of the pre-germination is reduced to four weeks. The tubers are then immediately ready for planting. The soil in the bed should then ideally be at least 9 °C warm.

Instructions for pre-germination with soil

Obtain vegetable soil in good time or mix mature compost and fine-grained sand in a ratio of 2:1. When the time is right, it goes like this:

  1. Fill the container or containers (crate, egg carton, etc.) with the substrate. So high that the tubers can be inserted about halfway.
  2. Place the tubers upright, without touching each other. One half of the tuber should be in the ground, the other half of the tuber should be visible.
  3. Pour the potatoes a little.
  4. Place the containers where they will find the ideal germination environment.
  5. During the entire period, check regularly whether the soil is still moist. If necessary, repeat the spraying with water.
Note: Look closely at each tuber before planting it in the ground to propel it forward. The half with the most eyes should look up. The green shoots will later form from the eyes.

Kira Bellingham

I'm a homes writer and editor with more than 20 years' experience in publishing. I have worked across many titles, including Ideal Home and, of course, Homes & Gardens. My day job is as Chief Group Sub Editor across the homes and interiors titles in the group. This has given me broad experience in interiors advice on just about every subject. I'm obsessed with interiors and delighted to be part of the Homes & Gardens team.

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top