Last updated on October 13th, 2021
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One of the best ways to grow hollyhocks is to use the seeds that a successful plant already provides you or buy some quality seeds from a seed specialist.
If you have successfully growing hollyhocks in your garden, you know that they require very little maintenance except for spraying them to protect them from hollyhock rust and that, if left to their own devices, they will live for about 2 or 3 years and then reseed quite effectively.
Preparing to propagate from seed
To learn more about when and how to collect seed as well as what to do with hollyhocks after flowering read my guide here, already got the seed – carry on reading this guide.
Before you start, fill a tray with compost and then water that tray well just to make sure all the compost is thoroughly moist. You might even get in there with your hands to mix it up. If you water after sowing, you might accidentally wash the seeds around the tray and then they stick together making them difficult to prick out later on. If you do forget to water beforehand use a fine rose watering can to water carefully.
When you sow the hollyhock seeds you want to do it individually, placing each seed at least 4 cm apart along the surface of the compost. As you’re doing this try to make a grid pattern, even better consider buying seed trays with separate modules, this makes potting them up later much easier and disturbs the fragile roots much less.
Don’t push the seeds into the compost or you won’t be able to see where they are, we recommend laying them on the surface as we can put a thin layer of compost over the seeds later. Start at the left on the top and then move across to the right and then back across until the tray is completely full. Then lightly cover with compost so that the seeds get enough access to light. We recommend using a compost sieve to get a fine even layer or use an empty plastic pot and sieve the compost through the holes in the bottom of the pot.
When you give them the proper spacing the seeds will germinate within around 2 weeks as long as you leave them in an area that’s warm, such as a windowsill or on a greenhouse with heat.
You can cover them with a piece of clear polythene if you don’t have a propagator as long as you leave it open and this will help keep them warm and stop the soil drying out. If you choose to do this method, check the trays every morning and every evening for germination after about two weeks. When they have germinated and sprouted, remove the plastic to grow them on further in the seed trays.
When growing from seed, hollyhocks take between 10 days and 14 days to germinate but they require another 4 or 5 weeks before they’re ready to be pricked out into their own pots, we recommend potting them into 9cm pots to grow them on further. If you notice that the roots are starting to show through the base of your tray, it’s time to move them.
When you’re ready to move them, handle them by the leaves and not the stems as you should with most seedling as they can be easily damaged. It might be best for you to try and tease out the roots and the seedling from the soil with a digger or pencil if you don’t have one.
At this point, place each seedling and its own 9cm container with good quality potting compost, pat it down and water it. It’s best to place them in an area at this point where they get all-around light. If you have sown the seed early enough, then by June they should be ready to plant outside, in your garden.
Last update on 2021-10-16 / Affiliate links / Images from Amazon Product Advertising API