I've just called the local GC to see if they have dahlia tubers in stock: " Yes, but we are waiting for paperwork , because they came from Holland, before we're allowed to put them out for sale " The continuing benefits of Brexit. Deep joy
I've read through this thread and got some excellent tips, thank you! I've just got three questions for your advice please:
1. When is the best time to pot up bought tubers for placing on a windowsill indoors? (I don't have a greenhouse.) I started them in early March last year but I think this was too soon as they got very etiolated before it was warm enough to place them outside.
2. Should I use ordinary MPC? (I'm planning to use peat free with extra grit added.)
3. One of my tubers failed last year due to rot so I assume this was due to too much watering despite me being careful! Should I just water once and leave until the first shoots emerge?
[@Plantminded I would just like to note there are loads of effective ways of doing it and lots of regulars here have great success with a wide array of methods.]
@Fire, I've had a look at Sarah Raven's video on the subject and think I've made my plan for success! (I would welcome any trade secrets from other growers of dahlias if you're browsing though please!)
@Plantminded It seems to be a bit of guesswork with when to pot up dahlias. Last year the frosts in the south went on right through May and lots of people got in a mess with having huge sprouting dahlias all over the house because we couldn't put them outside.
I keep mine outside and they usually start to show first sprouts in April and flower from May to Oct.
Some people water v little between potting up and getting green shoots, because, yes, the tubers can rot. Once you have strong green growth, you should be ok to water.
If you are planning to grow the dahlias as annuals or lift the tubers for the winter, then mpc (usually including its added fertiliser) should be fine. For lots of flowering, some people pinch out when the plants are young and use a liquid feed once a week. Regularly pick for the house / deadhead and they might flower to the frosts. If you're not keeping them in pots through the summer, wait until the plants are large before planting out as they tend to attract slugs.
If using pots, make sure the pot is appropriate size for the dahlias. The plants can range from 30cm to 2m+ tall so it's good to know what you are expecting (I made this mistake last year).
Please post pics of your plants. I hope that's useful.
Many thanks for your advice @fire. I'll try placing them outside in a sunny sheltered spot this year in late March and move them indoors if there's a threat of frost. This should avoid the weak etiolated shoots, with more natural light. I've placed my order! Thanks again for your help.
If you want to start them early and don't have a greenhouse, supplemental grow lights are really helpful. I started mine mid March. Starting them a bit later will save on energy though for sure.
Ordinary MPC is fine. Re watering, I think watering once and then waiting for shoots to appear sounds sensible. Maybe just add a little if the compost feels bone dry.
"What is hateful to you, do not do to your neighbour".
@Loxley I think timing for many people is a tricky thing. You need to keep them frost free. We in London had frost until the end of May last year. If you have a frost free greenhouse you'd be ok, but if you start them in the kitchen early, you may have yourself a forest of small trees by May and nowhere to put them.
I think it's like starting seeds for annuals very early. The exciting germination bit isn't a problem, but it can be a question of where to put all the small plants, once you have potted them up, no?
Posts
" Yes, but we are waiting for paperwork , because they came from Holland, before we're allowed to put them out for sale "
The continuing benefits of Brexit. Deep joy
1. When is the best time to pot up bought tubers for placing on a windowsill indoors? (I don't have a greenhouse.) I started them in early March last year but I think this was too soon as they got very etiolated before it was warm enough to place them outside.
2. Should I use ordinary MPC? (I'm planning to use peat free with extra grit added.)
3. One of my tubers failed last year due to rot so I assume this was due to too much watering despite me being careful! Should I just water once and leave until the first shoots emerge?
Many thanks in advance.
Ordinary MPC is fine. Re watering, I think watering once and then waiting for shoots to appear sounds sensible. Maybe just add a little if the compost feels bone dry.