Tag Archive for: Growing alpine plants from seeds

Early to mid- February is a good time for us, in cold Northern Hemisphere regions, to start seeds under indoor lighting. This way, by late April-May the seedlings can be acclimatized outdoors, and in some cases planted in the ground during the summer (fast growing species). Gaining 2-3 month of growth for our short season is a big plus!

This is an update of a 2022 post with few updates; also posted it in the Germination page now.

I have written about indoor sowing with other occasions, but a reminder is always good.
‘Warm germinators’ is the term used in
the BotanyCa catalogue to describe the dry seeds that will germinate at room temperature (+/- 17-21C) after a certain period of time (a few days to a few weeks).

Many species will germinate easily after a regular sowing, others require various treatments before sowing in order to germinate at warm.

I think it is a very good method especially for various rockery species which benefit from being planted in the ground at a young stage (various Arenaria, Bukiniczia, Campanula, Dianthus, Draba, Edraianthus Silene, Anthemis, Hedysarum, Oxytropis, Papaver species).
When
started in February, they can be ready for planting in the ground by June; some may even produce a flower or two!

Draba haynaldii seedlings by April

What treatments are used for various species, when starting them indoors?
Acid gibberellic treatment – an easy way to prepare a solution: Here
Hot water treatment for species with hard seedcoats: Here
Soaking and nicking the seeds, as well for hard seedcoats: Here
More advice for sowing small/fine seeds: Here

With so many light systems available nowadays, it is worth to try sowing and growing indoors a few species. It is most rewarding and also therapeutic to grow something new during the winter months!  Start with just 4-6 species if you are new at this. They will be perfect for a small trial-out ‘rock container’ planting in the summer.

You know the concept of going to do the grocery when you are not hungry, right? Your ‘plants budget’ will certainly improve when the garden centers start offering perennials in late spring!

*It can happen that species given as ‘warm germinators’ to not ‘comply’ to the rule, and vice-versa, ‘cold germinators’ starting to germinate at room temperature. Every year there is a new surprise. The source of seeds: wild coll. versus garden coll., growing conditions of the mother-plants and other factors, all can influence the germination pattern.
If a known ‘warm germinator’ refuses to comply, move the pot in cold location for 3-4 weeks (fridge OK) and then return it to room temperature. No matter what, it is best to keep your pots for 2-3 years if possible; some seeds can enter a second dormancy and will need multiple alternate cycles of cold/warm for germination.

What can we start indoors?

Glaucidium palmatum (older) seeds germination after GA3 treatment, Feb. 13, 2023.

The list below is not exclusive and it only contains cold hardy genera/species that I have personally germinated over the years at room temperature. I made notes for the species that I have started using GA3 (by habit, otherwise use cold/moist stratification) and those that will germinate best and faster if using a HWT (hot water treatment).

I recently included in the list Glaucidium palmatum – I just treated older seeds (2018/2019) with GA3 and there is almost 100% germination! It is not a fast growing species, but easy to germinate; the same goes for Podophyllum hexandrum.
Some of the species can be found in the SEEDS LIST.

 

Wash your pots (best practice for indoor sowing), prepare a sowing mix, labels, the seeds and then go! Start first with those species which take longer to germinate (or unknown) and leave the very fast germinators for early March (for example Papaver, Silene species).
Are you ready? Start sowing – the winter will be over in a blink of an eye and our gardens in bloom again :)

You can also find more ‘warm germinators’ by checking out the Germination guide of the Ontario Rock Garden & HP Society page: Here

February has arrived (with a vengeance) and I hope many are preparing to start their indoor sowings.

Silene suecica

I have written about indoor sowing before, but maybe is good to mention again the ‘warm germinators’.  This is the term used in the catalogue to describe the dry seeds that will germinate at room temperature (+/- 17-21C) after a certain (and variable) period of time.

I think it is a very good method especially for rockery species which always benefit from being planted in the ground at a young stage (Dianthus, Draba, Silene, Anthemis, Hedysarum, Oxytropis, Papaver….).

With so many light systems available nowadays, it is worth giving it a try. It is most rewarding and also therapeutic to grow something new during the winter months!  Start with just 3-4 species if you are new at this. They will be perfect for a small trial-out container planting.

Draba haynaldii grown-up seedlings

You know the concept of going to do the grocery when you are not hungry, right? Your ‘plants budget’ will certainly improve when the garden centers start offering perennials in late spring!

Also check out the Germination guide of the Ontario Rock Garden & HP Society page: Here
Advice on using acid gibberellic: Here
Hot water treatment: Here
Advice for sowing small/fine seeds: Here
Soaking and nicking the seeds: Here

 

 

*It can happen that species given as ‘warm germinators’ to not ‘comply’ to the rule, and vice-versa, ‘cold germinators’ starting to germinate at room temperature.

Echinops crispus seedlings

The source of seeds: wild coll. versus garden coll., growing conditions of the mother-plants and other factors, all can influence the germination pattern. When it happens, place the pot in cold location for 3-4 weeks. And, no matter what, it is best to keep your pots for 2-3 years if possible; some seeds can enter a second dormancy and will need multiple alternate cycles of cold/warm for germination.

The list below is not exclusive and it includes only contains cold hardy genera/species that I have personally germinated over the years at room temperature. I made notes for the species that I have started using GA3 (by habit) and those that will germinate best and faster if using a HWT (hot water treatment).

Acinos alpinus
Allium thunbergii and few other Allium
Aquilegia canadensis and most other Aquilegia – with GA3 treatment
Amphicarpaea
Arenaria
Arabis species
Androsace some species
Anthemis carpatica and other Anthemis species
Arisaema triphyllum and other Arisaema
Artemisia
Astragalus (with HWT)
Asphodeline lutea, A. taurica
Aurinia saxatilis
Alyssum
Baptisia australis (using the HWT)
Berkheya purpurea
Bukiniczia cabulica

Campanula, many species
Caragana (HWT)
Carlina acaulis
Calycanthus floridus
Centaurea triumfettii, C. orientalis, and other Centaurea species
Cerastium alpinum ssp. lanatum
Cercis canadensis
Cirsium
Clematis alpina and other Clematis

Draba species
Delphinium grandiflorum and other Delphinium species
Dianthus nardiformis
Dianthus superbus ssp. sajanensis, most other Dianthus species

Echinops crispus and other Echinops
Edraianthus graminifolius and other Edraianthus (not all species though)
Erinus alpinus
Gypsophila

 

 

So, get ready: wash your pots, have handy sowing mix, labels, the seeds and then go! Start first with those species which take longer to germinate (or unknown) and leave the very fast germinators for mid-February, early March. Good luck!

 

Fall has officially arrived and I thought it would be wise to start doing what I call my ‘petit inventory’ :) Lots of seeds have been sown this year and many have germinated. As usual, some seedlings have perished, while others have grown well; a few have been planted in the ground, and some are even flowering! (see Iris dichotoma and Scabiosa caucasica).

An inventory always helps me remember what I’ve grown during the year and it adds to the experience. In most cases, the inventory entails only 2-3 plants, or worse, 1 – truly ‘petit’! I will show a few from the alpine section for now.

Few Caucasian species are my joy and pride: Potentilla divina, Astragalus levieri and Eremogone lichnidea.

potentilla-divina

Potentilla divina a bit difficult to grow, I hope to get it through the winter

astragalus-levieri

Astragalus levieri – a high altitude species, easy to germinate but usually hard to establish; the young seedling was planted in the ground in May

eremogone-lichnidea

Eremogone lichnidea – another new species, I left them as they were in the seeding pot (some alpines react well to this treatment)

As well other species, like Silene jailensis and Paronychia cephalotes, have exceeded my expectations. I also have good hope to finally see the alpine thistle – Carlina acaulis, established in the rockery (seen in the Silene background).

silene-jailensis

Silene jailensis (a Crimean collection) – seedling planted early outside

paronychia-cephalotes

Paronychia cephalotes – another new one, the seedlings were looking so nice that I was afraid to prick them out and planted the whole seedlings pot in the ground.

As you notice, I have continued my experiment of planting asap very young seedlings in the ground, and it has proven again to be the better way to go, at least for me. They can have the roots going deep down fast and establish well throughout the season, while the ones left in pots are more difficult to manage water-wise, plus that the pots are not deep enough for their liking.

In the feature image: Artemisia umbelliformis (Alpine wormwood), another little alpine gem I’m happy to see doing well.

Next to come – the Chinese Podophyllum babies from the shady section!