Roots are loath to leave peat based compost-into soil.

[michael johnson]

Have any of you ever found that if you use a peat based potting compost in which the roots grow fine- after you have planted them out into the garden soil the roots are very reluctant to leave the compost to spread out into the surrounding soil.

Once or twice I have dug up the old root ball at the end of the season die off, and found it exactly the same as when I planted it with little or no root spread into the soil.

But if I use a partial mix of sterilised loam soil in the potting mix, together with a little grit, everything is fine with full root spread.

[travis]

MJ,

I don't know if you're specifically talking about tomatoes, or generally talking about plants transplanted from peat-based pottings into natural ground.

One of the principle points our local Purdue extention horticulturist makes at his shrubbery and tree planting seminars is to AVOID ammending the planting hole with excessive amounts of peat moss, composted materials, fine soils, etc., because of exactly what you have observed ... the plant's roots often will remain in the planting hole, circling around and around the root wad thriving on the soft, amended soil, and eventually strangling itself. This is especially true of many ornamental trees and nursery cultured shrubs.

I have not noticed this phenomenon in tomato plants myself. I have noticed it quite frequently in my basil plants, and basil is another annual crop that usually sets very deep roots when directly seeded into natural ground.

So ... I guess it bears a looksee if you're really all that interested. For my part, I could care less whether an annual gets root bound in a container or when transplanted into a garden from previously containerized media, just so long as the plant remains healthy and produces adequately. :wink:

PV

[Lomatia]

Some of these materials remain very attractive for plant roots. I once struck a number of cuttings (Australian natives) in rockwool and whilst it was sterile, clean and easy, the roots didn't 'invade' the potting mix when I potted them on and the plants failed to thrive. I must say though, the tommies that I have sown into those expandable peat discs (jiffy things over here) have kicked on.

[Polar_Lace]

Yes Michael,

This happens alot if you don't cut open the peat pots down the sides when you're planting things out into the garden. It even happens with jiffy pellets; you must always remove or cut the litltle liners they come in for the roots to spread out. I've experienced this also when removing plants from the little plastic 6 packs you buy them in. The only thing I can recommend to cure this is to make sure the next time you plant those babies out is to rough up the roots a little like bit of tugging at the roots to loosen them up.

Believe me; they'll thank you for it in a great display of flowers.