Save Tomato Seeds & Plant Stems

Save tomato seeds for next season

Many of us like to see how early we can produce our first ripe tomato each season. The totally obsessed, like me and quite a few

Save Tomato Seeds Nick

Others reading this newsletter, will have ripe tomatoes on the table around mid June – one or two even earlier in a good season.

I like to take seeds from my earliest fruiting plants, choosing the biggest fruit of course.

I’ve been doing this for many seasons with Red Alert and Black Cherry, taking seeds from the biggest and earliest fruit. I now have slightly larger tomatoes on my plants than when I first started, and thankfully they taste just as good!

Save tomato seeds from open pollinated varieties

Of course if you want seeds to grow true to type, you should save them from open pollinated varieties. When seeds from F1 hybrid tomatoes are saved and sown the following season, you never know what shape, size or flavour you’ll get!

If you are not sure whether the variety you are growing is open pollinated, a quick search online should soon tell you. Also, F1 seeds are a lot more expensive – some F1 seeds can cost around 50p each … you would certainly want those to germinate!

A few seed saving tips

A quick browse around the internet will produce conflicting information regarding how long seeds should ferment for. I like to ferment mine, keeping them in a glass container, for around five to seven days then use a tea strainer before setting them out on coffee filter paper.

Coffee filter paper

The filter paper doesn’t stick to the seeds like kitchen roll but still absorbs moisture well. Let the seeds  dry for about four or five days before putting them into a suitable container.

Glassine envelopes

I use glassine envelopes – the kind stamp collectors use. However, if you use an airtight container, you will need to make sure that the seeds are thoroughly dry, otherwise they may release moisture and rot.

Seed vigour

Seed that is saved from the previous season is usually very vigorous and you know exactly what you are going to get next season – you can never be sure from a shop bought packet as there can be slightly different strains of the same variety!

Seeds are alive and respire (see respiration) at a very slow rate until they are sown. Keeping them at a low temperature will prolong their vigour and life.

Stem thickness on tall varieties and balanced growth

We can tell a lot about a plant’s health by its appearance.

If you look at the stem of a tall variety, you’ll probably see that the thickness changes (or diameter to be more precise). Some parts of the higher stem may be thicker than the lower stem.

The stem displays the growing conditions and the amount of nutrients (especially nitrogen) a plant received at various stages of its growth.

The stem nearest the soil is often thinner than above, showing that the plant was probably started in less than ideal conditions (a UK spring perhaps!). There may be sections above where the stem becomes much thicker showing very good growing conditions and probably too much nitrogen.

In an ideal growing situation, the stem would be a consistent diameter or thickness – except at the growing tip of course.

Stem thickness is one of the ways to help measure the balance between vegetative and generative growth – between growing leaves or growing fruit!

Apologies if you have recently asked a question by email but have not received a reply. I’m in an area with a very poor internet connection at the moment!

That’s it for this week – I hope you are enjoying the best tasting tomatoes!

This article “Save Tomato Seeds & Plant Stems” was a previous season’s Newsletter.



  1. bill