Using straw and mulch to prevent soil born diseases.

[ChrisC_77]

In addition to helping plants retain water, does using mulch or straw help prevent soil born diseases? And is mulch or straw (either one) better for certain plants or does it really matter?

[rainbowgardener]

Having a mulch layer (straw is really just one kind of mulch, which is anything organic you lay on top of the soil) does help protect against soil borne disease and even insects like the squash vine borer and leaf miners, that have to pupate in the soil as part of their life cycle. The larvae drop down to the soil, dig in and pupate. The mulch makes it a bit harder for them to get to the soil or if they are in it, to get out to attack your plants. Not perfect but it slows them down, fewer will complete the cycle.

For things like pumpkins and melons that sit on the soil, mulch keeps the fruit from getting rotten where it touches the soil.

I prefer straw to bark mulch as it breaks down to feed the soil easier. It's why we call them straw-berries, because growing them on straw was traditional.

[JONA878]

Many pathogens rely on water splash to disperse their spores. That is why most fruit farmers mulch the strips below their trees or grow the grass right up to the trunks prior to harvest. This stops rain and wheel splash from infecting the fruit.
Things like canker, collar rot and bacterial canker are all soil born diseases that can spread this way.
In strawberries straw mulch helps to act as a buffer against Phytophthora ,Red Core and Grey Mould.

[imafan26]

Mulching helps the soil retain water. A good thing as it means you use less water. But a moist soil can also mean more mold and fungal disease if it rains a lot. The mulch will help with the splashing of the soil onto the leaves and transferring the fungi from the soil back up to the plants.

Mulching can also provide hiding places for things like slugs and snails so you will need to be on the lookout for them.