20 yrs gardening in a difficult zone 5a, i consider myself an 'insurance' gardener... For summer and winter squash, melons, pumpkins...., i have 12 well spaced mounds... 5 seeds in each hill last weekend...5 more will go in this weekend...and a seed starting tray i started a couple weeks ago. They tray is doing well and still small. -these crops do not like transplanting at all but i do it close to planting time, soil warm, temps. 4-6 inches is perfect. Really not much trouble but i avoid having to purchase with so many seeds anyway by sharing and exchanges and seed saving last years crop seeds. Too much moisture and rain this time of year for me, we often get seed rot...they turn to mush if i look for them after no germination... A good year all comes up fine... With multiple seeds in a hill, i can then select the strongest plants and cull the others... After up and strong and surviving cutworms and such maladies...3-4 plants per hill.

Many people will WS straight into a container. They do put some sort of a greenhouse-creating cover on it. Whether you plant straight in the ground or a pot, the seeds are at the very surface, where it dries out fast, and they need daily or almost daily watering if you do not have a cover to hold the moisture in. You could do that, or just stretch some vented saran wrap across your pots, or use a clear garbage or dry-cleaning bag. Depending on how sunny your spot is, you will need big vents at this time of year since a warm day plus a very sunny spot may cook the seedlings. Most people recommend a soilless or mostly soilless mix for containers, if what you have is actual soil, I would mix it with some perlite or peat or both to make sure it stays pretty fluffy all season.

I applaud you for the effort you have gone to, to get your grevillea growing in a pot. When you water the pot, perhaps you could try immersing it in a bucket of water, until all the air bubbles stop coming out of the pot. This really is the best way to water pots. Sometimes potting mixes become "hydrophobic" which means they repel water, and it is difficult to water pots from above when this is the case. Perhaps you could try buying a smaller Grevillea banksii, the one in the picture is large and does look like it should be in a bigger pot. A smaller plant might be easier to handle and would have a greater chance of getting used to its situation, early on. If you buy a plant that is reasonably advanced it has become used to its place in the nursery. Then you take it home and plonk it on your balcony and it could go into shock. A word about the cow manure, make sure it is well rotted. You sound like you are interested in plants, perhaps you could do some research into your "local species", I am sure there are horticulturists in Brazil who must be interested in preserving the local plants. Sounds fascinating. Drainage is important too, so let the pot drain when you have done the immersion in the bucket. It is equally important to make sure the pot does not have too much watering. So make sure there are dry periods between watering. You could stick your finger into the potting mix to get an idea as to how wet the mix is. I have seen this tree growing near me and it is huge. Here is a link that might be useful: Plants of Cerrado region.

Great photos, fabulous species of Gesneriads. You sure have a Green Gesneriad Magic! Love this plant. And the berries are tasty and sweet - would eat them all - if not the the desire to save the seeds... The only issue for people who want to try it - it needs a decent humidity - otherwise the edges of the leaves scorch and brown up. i would say 50% humidity is good. Georgia has an excellent humidity - but Colorado doesn't - so for me Corytoplectus does better on the wick and mats surrounded by other plants creating an ambient humidity.