Beginners greenhouse

[Ange65 0]

I ve got a greenhouse up and running but not really sure how to manage it. Learning alot by my own mistakes - drowning seedlings, watering in full sun etc etc. When do I open door for air to get in?  My potatoes are thriving, now got them outside and water twice a day,  when sun's left the garden and early morning. Cherry tomatoes are doing well. Lettuce, meant to be easy but 2 plants out of 40 are thriving, rest are a disaster.  Flower seeds are a disaster too. Any advice appreciated. Wanted to grow flowers for my own hanging baskets but it's not looking very good at all. Thank you in advance for any advice.

[Thorpist 72]

Lettuce don't like  it in a hot greenhouse, they are best sown in spring or late summer.

if you are trying to grow summer bedding annuals you will find it difficult without heat during the cold nights.

We had high daytime temperatures during February which killed quite a few of the plants I had put in the greenhouse for winter protection, the temperature fluctuation can be extreme.

Remember greenhouses get  very warm and need ventilation even early in the season.

Have you considered buying in small plugs, these need growing on in the greenhouse until after the the last frost .

[Ange65 0]

What are 'small plugs'? Thank you for the advice, I ll get my lettuce outside before they wither away.  Is it right that I should only open it when there s condensation inside? Or should I open it everyday regardless?

[Ange65 0]

Oh and another thing - my potatoes are starting to flower.  When are they ready to dig up?

[Janus 28]

@Ange65

Plug plants are basically young plants in individual cells, as opposed to in a seed tray or loose. The method means you won`t disturb the roots when removing

https://www.google.com/search?q=plug+plants&client=firefox-b-d&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiE7dyC5criAhXCQhUIHaWHBgEQ_AUIESgC&biw=1280&bih=910

 

It is warm enough for most flowers to be outdoor now. Things like toms, cucumber, peppers etc will be ok in a greenhouse. You need plenty of ventilation in the daytime in the greenhouse.

[Chez2 10]

There are some good gardening magazines, some more basic, some a nice mix or articles. We have amateur gardening and Gardening Which? There are some good Facebook groups eg Greenhouse Gardening UK or more speicif groups. There is also a good group called plants for sale, swap, buy South Yorkshire.

 

An electric propagator will be fine to give you a good head start. You can get narrow ones to fit on your house windowsill.  

[Ange65 0]

Thank you all for your advice. 

[barry-333 10]

I have a lot of 'Gardeners World' magazines that have been passed on to me and you are willing to have them

I am in Sheffield 8 Norton

[Thorpist 72]

About 12 weeks for first earlies , generally around the time they are flowering.

Have a rummage  around if they are about the size of an egg start harvesting as and when you need them.

Second earlies  july august and the maincrop leave until the tops have died back.

After picking maincrop leave the potatoes to dry on the surface to toughen the skin ready for storage .

I store my main crop in old dried potting compost saved from the previous year. You could I assume use shredded newspaper or anything to keep them dark dry and preferably not touching just in case of a rotten one affecting the rest .