Hello,
I have flower seedlings growing in my greenhouse in a heated dome. Marigolds, pansies, petunias, lobelia and alysum. My problem is the alysum are tall, weak, falling over and dying and the lobelia seem to be on pause. Do I need lights, even though the greenhouse has daylight on all sides.

How tall should any seedling be?
When can I take them off the heat, my greenhouse read 3.5 oC last night.

"kerrygirl" wrote..


Hello,
I have flower seedlings growing in my greenhouse in a heated dome.
Marigolds, pansies, petunias, lobelia and alysum. My problem is the
alysum are tall, weak, falling over and dying and the lobelia seem to be
on pause. Do I need lights, even though the greenhouse has daylight on
all sides.

How tall should any seedling be?
When can I take them off the heat, my greenhouse read 3.5 oC last night.

The light levels in the UK at the moment are not good most days and then you
have the plants inside a greenhouse and then in a dome so two things
reducing the light levels reaching the plants still further. Coupled with
heat making them grow, they are hunting for light.
Personally I wouldn't plant seeds of those summer bedding yet, April at the
earliest, but then I won't chance the frost until Chelsea.
--
Regards. Bob Hobden.
Posted to this Newsgroup from the W of London, UK

Thank you Bob for replying. I guess I am in a hurry

On 21/02/2015 21:50, kerrygirl wrote:
Bob Hobden;1011722 Wrote:
"kerrygirl" wrote..-


Hello,
I have flower seedlings growing in my greenhouse in a heated dome.
Marigolds, pansies, petunias, lobelia and alysum. My problem is the
alysum are tall, weak, falling over and dying and the lobelia seem to
be
on pause. Do I need lights, even though the greenhouse has daylight on
all sides.

How tall should any seedling be?
When can I take them off the heat, my greenhouse read 3.5 oC last
night.
-
The light levels in the UK at the moment are not good most days and then
you
have the plants inside a greenhouse and then in a dome so two things
reducing the light levels reaching the plants still further. Coupled
with
heat making them grow, they are hunting for light.
Personally I wouldn't plant seeds of those summer bedding yet, April at
the
earliest, but then I won't chance the frost until Chelsea.
--
Regards. Bob Hobden.
Posted to this Newsgroup from the W of London, UK

Thank you Bob for replying. I guess I am in a hurry




Sweet peas do pretty well on low light and low temperatures but, as Bob
says, summer bedding plants generally don't. Everything races away when
the time is right, but not before.
I've been rearing some abutilon indoors, and I've gradually lost 95% of
them, but the odd few that have survived look as though they mean
business. Natural selection at work I guess

I have decided to remove the dome fully and reduced the under heat to 24 oC. I will have to see how this goes!

On Sun, 22 Feb 2015 16:59:37 +0100, kerrygirl
wrote:

I have decided to remove the dome fully and reduced the under heat to 24
oC. I will have to see how this goes!


Personally I think 24 c is still too warm, I would wait a bit, and
then use 20 c , grow them 'slow' you will get better plants

In article ,
says...

On Sun, 22 Feb 2015 16:59:37 +0100, kerrygirl
wrote:

I have decided to remove the dome fully and reduced the under heat to 24
oC. I will have to see how this goes!


Personally I think 24 c is still too warm, I would wait a bit, and
then use 20 c , grow them 'slow' you will get better plants

Frankly instead of heating to 24 C she would be better to write off the
plants as a learner's mistake (we've all done it), save her fuel bill,
and re-sow later. Light levels and out door temps will be higher. Then
she can grow sturdy plants under cover at less expense, and have them
at the right stage when it's safe to plant them out. After last frost.

We're in mid Feb; frost-tender annuals will require cover/protection
for at least the next three months.

Janet.

"Janet" wrote

says...

kerrygirl wrote:

I have decided to remove the dome fully and reduced the under heat to 24
oC. I will have to see how this goes!


Personally I think 24 c is still too warm, I would wait a bit, and
then use 20 c , grow them 'slow' you will get better plants

Frankly instead of heating to 24 C she would be better to write off the
plants as a learner's mistake (we've all done it), save her fuel bill,
and re-sow later. Light levels and out door temps will be higher. Then
she can grow sturdy plants under cover at less expense, and have them
at the right stage when it's safe to plant them out. After last frost.

We're in mid Feb; frost-tender annuals will require cover/protection
for at least the next three months.


I agree, it's a common mistake to make for new gardeners and not helped by
Garden Centres selling tender plants from April or earlier. I've seen so
many new allotment gardeners planting stuff out some weeks too soon and then
losing it because of a frost, some also don't seem to learn and do it year
after year which I find strange. My greenhouse is heated to 10°C min because
of orchids etc in there and that is what any young plants have to deal with
once germinated in the propagator.
--
Regards. Bob Hobden.
Posted to this Newsgroup from the W of London, UK