Growing on Seedlings

Hi All.
Your opinions please. Last year I grew some annual seeds under heated propagator in garage for the first time. Made 2 mistakes, First was once seedling came up I did not give enough ventilation and once plants started to grow they went rotten as it was too damp.
Second was as the plants grew they leaned towards the window which they were next too and became leggy.

For the coming season I have learnt these lessons. Now I know there has been a lot of post`s on grow lights and some very good DIY clips on you tube of making grow lights from PVC tubing which is very simple and takes apart.

I know I could buy them readymade but I would like the satisfaction of making them as that is the way I am. Now my wifey tells me I do not have to do this as I could build a table which again comes apart for storage during the summer and put the small plants in trays in the conservatory as they would have enough natural light to make them grow upright and sturdy.
This I must admit does seem a good idea as table could be lined with polythene to stop water from trays running on floor and you can turn the trays very easy every day.
Not sure which way to go? Has anyone grown their seedling in the conservatory or would you think the grow light method is better. I would have thought that since heat is turned off on propagator once seedlings appear the conservatory would be ideal. I doubt if we would have the conservatory heating on a you are looking at say beginning of May-ish.
Thank you

 

I've got 4 "Growlux" tubes in standard double fittings, they work well. I wouldn't be in such a rush and plant later, later planted seeds always seem to catch up with the earlier planted seeds and seem to be more rubust.

Cheers, Tony.

 

Trogre, when using a heated propagator you should remove the seedlings as soon as they appear above soil as the heat and cover will make them grow leggy. Don't worry if all the seedlings aren't showing as germination will probably have taken place and they will appear in a few days. They should then be given as much light as possible but not direct sunlight.

 

Conservatory light will be better than artificial light (and free - saving both capital cost and running cost).

However, early in the year (before, say, March) the light is weaker, and artificial light can be helpful for people starting very early, or wanting to over-winter things. If you already have artificial light (for over wintering say) then using that on Seedlings during night-time hours (during the spring) can supplement the sun they get during the day and boost the rate at which they grow.

Only issue with conservatory are whether it will be warm enough (assuming you don't actually heat it? if you "live" in it then that won't be a problem), or if it gets very hot during the day (because you are at work and not around to open the vents if the sun comes out full-power in the middle of the day).

You may also find that the sun is very strong for very young seedlings (e..g that came out of an indoor propagator when they germinated). You can put them UNDER your table for a day or two, so that they are in some shade

I doubt that you could make a grow-light rig cheaper than you can buy one. You need the tubes, and "starters"/ballast, and they aren't cheap (unless you have a few lying around) plus wiring and supports. It is best to use T5 growing tube lamps (which have plenty of light in the Blue colours, which the plants need for growing, and which ordinary "strip lights" may not have so much of)

 

Which seeds are you planning to sow Trogre ? March the first is a target seed planting date , due to the improved light levels . I plant the majority of my seeds around this date.

 

Trogre - why not have a go with your suggestion of growing them in your conservatory. When I sow seeds I never sow the whole packet, I always hold some back for another one or two goes. So why not try some early and leave some seeds over to sow on, say, 1st March as HarryS suggested. This is also the date that Christopher Lloyd used to recommend. I find gardening is always a matter of trying slightly different methods.

I sow quite a lot of seeds with, and also without grow lights. I use a mix of 70% compost and 30% sharp sand to help drainage. I water the compost before sowing and then don't water again for several weeks. I put a transparent top on the seed tray which keeps the moisture in, and occasionally I spray it with a dilute solution of a copper compound such as Cheshunt compound. This does two things, the spray replaces the very small amounts of moisture that are lost over time, and the copper compound is an antifungal agent which helps to prevent damping off (ie seedlings dying early).

I know everyone says you must remove the cover when the seeds germinate, but I tend to leave the covers on for several weeks, although you have to remove them every day to allow replacement of carbon dioxide, which is what builds the seedling. I leave the tops on because it is warmer, especially with a heated propagator, and also it cuts down on watering. I am just lazy - but I have also been lucky and had very little problem with damping off.

 

Interesting point PeterS. I do exactly the same, and have never understood the "whip the cover off the moment they germinate" camp. Same people will probably spend weeks hardening plants off before they go outside, why would they suddenly take a tiny seedling, with hardly any root, from 100% humidity to the dry atmosphere of a room in 0 seconds ... poor things!

I do progressively open the "little vents" on the top of the clear plastic domes once the seeds have germinated (if no vents I just put the domes on slight askew so there is air gap at the bottom), and I take the domes off if they are in bright sun during the day (although I don't let them have full sun, all day, until quite a while after germination)

 

I also use March as a target date for most of seed sowing, the exceptions being stuff like Cannas, which I will start in early Feb or even late January. I have been know to experiment though and try sowing seed at other times of the year (I'm going to sow some Musa seed this week), in theory perennial seed can be sown in the autumn - a time when the seed is naturally shed by the plants, some may not germinate until the spring but others do and make slow progress over the winter and it gives them a head start in the spring.

I also leave them under cover for a little while after they germinate, after a few years experience you can almost tell by looking at them when they look happy and when they're saying "oi put the lid back on"

 

As I said earlier - I think there is a lot of trial and error in gardening. There are frequently many slightly different ways to do the same thing. Very often there is not a single right way - you experiment and and then use the method you are comfortable with.

Another aspect is the compost. I buy, usually the cheapest, compost and find that there are many different sorts. There is sometimes a debate as to which is the best. Quite frankly - I don't know. Without repeated controlled experiments I have no way of knowing. All I do is run it through my fingers and some feel nice and some don't. But that's not neccessarily how a plant feels it.

Quite frankly I am not sure it matters that much. You don't want lots of lumps for seedlings - but you can sieve them out. My feeling is that, as you can grow plants without any compost at all in hydroponics, it probably doesn't matter that much. But I am sure that others will disagree.

The one thing that is important is the drainage, which is why I add extra sharp sand. Even with the cheapest compost seedlings have usually done well for me. There is always a small percentage of failures - but I believe that sometimes that is due to seed that was never viable. A good test of that is to try to germinate them on moist paper in a polybag. If the seed goes mouldy, inspite of spraying with Cheshunt compound and with no compost, the mould was most likely already in the seed.

My only major failure was with some very cheap compost from Focus, a few years ago. Even after mixing with sharp sand the compost looked like a mud flat after it was watered. Despite my misgivings I sowed a number of batches of seeds (part of a packet only) and many of them went mouldy. So my conclusion is that you do need good drainage and musn't over water seed compost, but otherwise most stuff is OK.

 

I use cheapest MPC compost from closest garden centre and only when it is on special offer! I try to buy all-I-need for the year in Autumn, as I think the quality is better (perhaps it hasn't sat 10-pallets high being compressed, or sitting out and soaked by rain, or whatever, which the Spring-bags seem to).

I mix with 10% (by volume) perlite to improve drainage. I tried some batches one spring pricked out to 3" pots (as I usually do) with half in straight MPC and the other half in 10% perlite. I expect if I could have watered them carefully, and tended to them several times a day, they would have been identical, but with my now-and-then time-poor gardening style there was a clear advantage from the 10% perlite ones. Sand would be the same, just something to keep more air in the mix (which careful watering and TLC could also accomplish I expect)

However, I am fussy about my seed sowing compost. I buy John Innes Seed Compost - a very sandy soil mix. I don't add anything to it, and I only use it in seed trays (so I'm not trying to fill a whole pot with it, just the couple of inches depth of a seed tray). Fine/Small seed is broadcast, and comes up like cress of course (i.e. plants-per-unit-area = Lots!) but the bigger seeds I sow individually, neatly spaced, and they are only 1/2" - 1" apart - so not much seed compost required. I use one small bag a season, although I do reuse it after pricking out (no reason not to IMHO, no disease, it had no/little nutrients in the first place, only risk is of ungerminated seeds coming up "late" in the next batch)

I find that the sandy J.I. Seed Compost is a joy when pricking out. It falls off the roots, whereas I found that sowing in compost with more peat clings to the roots, and roots from two adjacent plants "sharing" a lump causes damage during pricking out.

But like PeterS says, its what you have tried that you like, and which you find works, and then stick to

 

I remove the lids daily to ventilate the propagators . So the atmosphere inside would be slightly oxygen rich and CO2 depleted ?

I normally use B n Q seed compost + perlite . This year I used the new Westland Surestart +25%seed compost , like a few others on here , not sure if I noticed any improvement though.

Now has anyone got the Which results of the seed compost report below ?

http://www.which.co.uk/news/2012/01/seed-compost-274839/

 

My personal thoughts are growing under lights is only worth while for seeds of tender perennials, in order to get an early start and hope for flowers the first year.

I've managed reasonably well over the years without lights.
But I do use a heated propagator.
You just need to sow later, and not try to rush things, late March and right through April are good times to sow.
You need to bear in mind that a heated environment will be required for seedlings once they leave the propagator, and that would be best in good natural light at that time of the year.

 

The only time I've had damping off is when I've left seedlings in the propagator after germination, which is why mine are out as soon as they show, they are then left in my unheated but light back porch until they have acclimatised to the temperature change for about a week. I then pot them on and leave them in the greenhouse until frost has gone. I have very few losses.

Each to their own way of doing things I think Kristen.

 

Absolutely. I'm loath to change, unless I read something that I find very compelling, or have spares that I care to experiment with. If it works for me I'm not keen to change, and I'm sure other folk likewise

Always interested to hear other people's methods though; I often pass on what other people do, in case that strikes the person as a better way, and I tune my own methods now and again. But something radically different is hard to persuade me to try!

 

Pete - I would agree that in the normal way there is no need to grow seedlings under lights. I tend to only do it for selected things such as tender plants as you mentioned. The bulk of my seed growing in in the traditional way starting on 1st March.

Having said that I do enjoy my light box because, in the winter, I can be gardening inside in the warm, when snow and frost is covering the garden.