How do I grow Amaranth successfully without it becoming invasive?

Question

So I found a really pretty herb called Amaranth. It turns out it's edible and super healthy. Sadly I'm not sure how to grow it and what I can and can't grow near it. And I am talking about the edible plant not its sister plant which is an invasive weed. Should I build a raised box and tarp it under the soil to keep it from rooting elsewhere?

Answer 1

Hmm, well I'm a bit confused, so let's clear a couple of things up. First, all Amaranths are edible, including Dicentra spectabilis (an amaranth) and pigweed. Second, most are just annuals or short lived perennials, in particular the leafy kinds you want to grow for their leaves, such as Amaranth dubius, so the only reason they might be 'invasive' is because, in the wild as pigweed, they flower and set seed, and the seed germinates and therefore there are more plants over a wider area.

Given you'll be growing it to eat, for salad use, the leaves are best cut when young, so you can remove the whole stalk when it gets to about 10 inches and use all the leaves, or 'cut and come again' at a smaller size. If you want the seeds, collect them once they're ripe, and to get seed, you'll need to leave some of the plants to flower - and at that point is when you need to be careful - get that seed before it distributes itself naturally. If you don't want the seed, then just keep cutting off the flowered stems - you can't eat the flowers, but you can eat the buds (apparently, I don't know, I've never tried them).

Most varieties are better off in a soil that's nearer to average than rich, so reasonable, ordinary garden soil should do just fine, but it will grow better in moist but well drained ground. Also prefers (for leaf crops) about 5 hours of sun a day.