I'm in usda hardiness zone 7a in NJ. Can you use plastic mulch for plants in the vegetable garden without drip irrigation or soaker hoses? If so how do you water plants with plastic mulch?
Yes. I've never had drip irrigation, but I have used plastic much some years. If watering is needed, pour it in the holes where the plants are (or I suppose you could make other holes for it, but I never have). Or you could park a soaker hose under the plastic and connect it when needed. You can shape the ground such that most water landing on the plastic runs in to the holes (ie, dish rather than mound.) Water landing on the paths will also migrate sideways eventually. Of course, the plastic also slows the ground drying out under it.
Making a dish shape for each plant is one of the things I was considering. Have you actually done that? Apr 11, 2015 at 13:50
1Yes. The whole bed is "raised" but the top of the bed (other than the extreme edges) is dished towards the plants. An inch or 2-3 cm will do it.– EcnerwalApr 11, 2015 at 15:18
Question for both you and @FiascoLabs Do you leave the plastic on throughout the whole season or do you remove it in the summer when temps become very hot? Apr 17, 2015 at 13:59
All summer - until after the tomatoes are gone, which is usually after frost. Pull dead tomatoes, then roll up plastic. When the temps are very hot, it's mostly shaded by foliage.– EcnerwalApr 17, 2015 at 14:04
This is on loam, may not work well on sandy, well drained soil.
The way I did it was to have shallow trenches on either side of the raised bed (4-6in berm) my tomatoes were planted in. The berm was prepared with shallow depressions where each plant would be placed and the mulch film rolled out over the top of the berm with enough slack to let it sag into the depressions.
The plants were planted through X cuts in the mulch plastic just big enough to allow a 4" hole to be dug to accept the root ball. Fold the plastic back in place to cover the root ball, water at the plant base as till you're past transplant shock and the plants are established. Put cages in place.
Water the trenches to saturation and the water will capillary up in the soil. It was pretty nice having a totally weed free operation and you can check for soil moistness by feeling in around under the mulch next to the plant base.
The mulch also cuts way back on evaporation (nothing is worse than bare soil) and let me deeply water once a week during the hottest part of the season with no signs of moisture distress.
Both answers were very helpful but Ecnerwal's answer was more suited to my garden setup. Apr 17, 2015 at 14:06